Research and Development of New High-quality Short-season Cotton Varieties and the Industrial Application of High Efficiency Technologies in Shandong Province

Guifeng WANG Guofang HAO Shaohong ZHANG Yongming LI Han GAO Kaichun LI Yong FANG

Abstract Through the analysis of the impact of changes in the cotton planting industry on cotton production structure and benefit in Shandong under the national cotton production pattern in past ten years, based on the guarantee of food security and the overall ecological regional layout of Shandongs agricultural characteristic and advantageous industries, we proposed that through the development of high-quality short-season cotton and the industrial application of high-efficiency technologies, a green and high-efficiency farming system should be established to comprehensively reduce cotton planting costs, improve comparative benefits, and realize green and efficient optimization technologies that unify the stable production of cotton and high-quality cotton supply and the industrial path supported by the new industrial model. It is aimed to speed up the upgrading and transformation of the existing traditional cotton cropping system, reconstruct a ternary structure of grains, economic crops and fodder in the ecological suitable cotton areas and sub-suitable cotton areas in Shandong, and maintain a series of new green and ecological cotton rotation industrial models including the “double security” of the grain and cotton industries, the ecological “double superiority” of cotton and fodder”, and the high-efficiency "double increase" of cotton and garlic, providing a certain foundation for the research on technological integration innovation and industrial structure optimization of the green, efficient and high-quality development and transformation of the cotton industry in Shandong during the "14th Five-Year Plan" period.

Key words Shandong Province; Green; High efficiency and high quality; Cultivation system; High-quality specially-purposed; Short-season cotton; Industrialization

Received: June 23, 2021  Accepted: August 28, 2021

Supported by Shandong Provincial Cotton Green, High-yield and Efficient Creation Project (LNMZ［2017］5).

Guifeng WANG (1964-), male, P. R. China, researcher, devoted to research about cotton industry technology and industrial economy, genetic breeding and farming application.

*Corresponding author.

Cotton is a basic bulk agricultural product with the attribute of a public product in China. The economy of cotton industry is related to basic peoples livelihood security and the safety of basic industrial systems, and plays a decisive role in the pattern of agricultural and rural economic development.

Chinas cotton production ranged from 400 million kg in the early days of the founding of the Peoples Republic of China in 1949 to 2.17 billion kg in 1978. It has maintained a level of 5.5-6.0 billion kg until the 20th century. Cotton productivity has continued to increase, which not only meets the needs of residents, but also provides strong support for the sustainable development of the middle and lower reaches of the industry with green basic raw materials.

Shandong Province is a major province in Chinas traditional cotton production, consumption, and textile and garment exports. Its total economic volume and market competitiveness of the cotton industry ranks among the top in China, providing efficient supporting organic support of the domestic market of the industry for the transition in national cotton ecological production pattern and the stable economic development of the entire cotton industry. In the 1980s, Shandongs cotton area and output accounted for a quarter of the country, and once ranked first in the country for 12 consecutive years, and its export volume accounted for one-fifth of the country. Since the beginning of this century, the intensive adjustment of Chinas rural economic structure and agricultural industry structure, changes in domestic and foreign cotton resource market integration, market mechanism adjustments, and changes in natural climate conditions have led to a substantial adjustment of the national cotton regional layout, and moderately concentrated adjustments in the inland cotton areas. In 2020, the area and total output of the northwest inland cotton area (mainly Xinjiang and Gansu) accounted for 79.45% and 87.83% of the country (Table 1), respectively, and the cotton planting industry in Shandong Province had shrunk to the cotton sown area and the total output accounting for 4.50% and 3.10% of the country, respectively.

The changing tendency of reduced scale of cotton production and the concentration and dispersion of cotton planting areas in Shandong Province is basically a reduced version of the changes in the national cotton area. Since 2008, the provinces cotton production has been shrinking and fluctuating at an annual scale of 53 300 hm2. From 2016 to 2020, the sown areas in Shandong Province were 279 100, 174 700, 183 300, 169 300, and 142 900 hm2, respectively, and the total outputs were 329, 207, 217, 196, and 183 million kg, respectively. The cotton planting area and total output of Shandong Province in 2020 were only 10% of the peak values in 1984 (1.712 million hm2 of cotton planting area and 1.725 billion kg of total output).

According to the statistics of the public management service system for cotton production in Shandong Province, since 2015, the planting scale of the two-cropping and high-efficiency cotton-garlic interplanting area in southwestern Shandong has accounted for 50% of the province and has increased year by year, being 52.0%-53.6% in 2017-2018, 60% in 2019-2020. In 2020, the "double flowering" ecological production of intercropping cotton with peanut in the old course of the Yellow River in northwestern Shandong Province, a "double increase" optimized two-cropping industry model, supported the cotton planting scale in the northwest of Shandong Province at the highest point of the cotton planting area in northern Shandong.

There are three main reasons for the changes in the national cotton production pattern and the inland cotton industry. First, the advancement of science and technology has promoted the further optimization of the division of labor in cotton production areas. The prices of production factors in the mainland have risen, and the traditional cotton production mode of single cropping has high production costs and low comparative benefits. The second is the national grain and cotton advantageous ecological regional layout, which has led to the orderly guidance of the national cotton production pattern to optimization and transfer of the northwest inland cotton planting industry and the effective adjustment of the inland agricultural planting structure. The third is that the inland cotton industry has the disadvantages of single main cultivar, unbalanced high-spinnable property structure of the fiber quality index system, traditional production methods and obvious disconnection with the localized cotton secondary and tertiary industrial chains［2］.

Based on the national principle of ensuring food security and ensuring the stability of the supply chain of the industrial chain, combined with the current situation of the planting area of Shandongs planting industry in the past ten years, starting from the overall situation of ensuring the stability of Shandong Provinces grain production and the overall situation of the advantageous industrial crops of Shandongs agricultural characteristics, we will speed up the research and development of new varieties of high-quality short-season cotton and the application of high-efficiency technology industrialization, so as to change the traditional high-cost cotton farming system, establish a green, high-efficiency and high-quality farming system in Shandong Province, realize the ecological integration of the cotton industry, and establish a new type of green, high-efficiency and high-quality cotton production system under the framework of the provinces "grains, economic crops and fodder" ternary ecological and high-efficiency industrial system, which can improve comprehensive cotton yields and coordinate and stabilize new forms of cotton planting, and is an important innovation path for the optimization and integration of agricultural high-efficiency technologies in a certain period of social productivity［3-4］.

Development of High-quality Short-season Cotton is an Effective Technology and Industrial Approach to Break Through the Bottleneck of the Inefficient Development of Traditional Cotton Production in Shandong Province

Short-season cotton has a shortened growing season. It originated in the United States and the former Soviet Union. It has compact plant types, short plants, and short internode fruit branches. The first fruit branch has a low planting node position and fewer leaves. Short-season cotton has a longer superposition of vegetative growth and reproductive growth, faster growth from flowering to boll opening and reproductive growth. The harvesting traits of bolls are concentrated, and the growth and development period can be shortened by more than 1 to 2 farming seasons relative to the Chinese lunar solar terms. Short-season cotton belongs to the cotton planting types of Gossypium hirsutum Linn. with early maturity.

The industrial application of new high-quality short-season cotton varieties with high-efficiency technology can not only achieve the integration of the entire cotton industry chain, but also form a new green, high-quality, high-efficiency farming system［4］, and effectively coordinates and resolves the main contradiction between Shandongs large population and small land and field crops competing for land and transforms the traditional one-cropping cotton planting area in northern Shandong and the cotton intercropping model in southwest Shandong into a mechanized two-cropping planting system, thereby improving the comprehensive economic and ecological benefits of cotton production.

It is necessary to promote and accelerate the development of high-quality short-season cotton varieties with early maturity and stability, stable yield, high quality, and wide stress resistance, and carry out traditional farming system innovation, which has become the research direction for the development and application of local modern cotton breeding and the further application of cotton hybrid advantages［4-5］.

Natural ecological conditions of agriculture in Shandong Province and the spinnable property structure types of cotton

Since the 1990s, the cotton bollworm in the main cotton-producing areas of Shandong Province has suffered severe damage and the effects of Verticillium wilt. The quality of cotton fields has declined, the production cost is high, and the comparative efficiency is low.

In Shandong province, the accumulated temperature of ≥15℃ is 3 500-4 100 ℃, the frost-free period is 180-230 d, the annual sunshine hours is 2 200-2 900 h, and the accumulated temperature of ≥15℃ in most counties is 3 500-3 600 ℃, which can only meet the heat requirements of early maturing varieties. The annual rainfall is 500-800 mm, mostly concentrated in July-August. There are also big differences in rainfall distribution, soil and other ecological conditions. Drought occurs in late spring and early summer, and the sunshine in spring and autumn is moderate, which is conducive to cotton growth and bill opening, but gradually decreases from south to north with a large difference. The temperature drop in late autumn is not conducive to autumn boll maturity and fiber maturity. The soil is mainly loamy fluvo-aquic soil. The cotton area in northwestern Shandong is mainly sandy loam saline soil, and the cotton planting areas in the Yellow Triangle of North Shandong and the Bohai Sea Rim are mainly coastal saline-alkali land［4］.

According to relevant data reported by the State Administration for Market Regulation, the quality indexes of cotton fiber in Shandong Province in 2018 were as follows: breaking strength 29.29 cN/tex, cotton length 27.85 mm, micronaire value 4.9, low yarn strength, and length uniformity index 82.17%. According to the national cotton standard color grade, among white cotton, light stained cotton, light yellow stained cotton and yellow stained cotton, white cotton accounts for 46.27% and light stained cotton accounts for 51.05%［6］.

At present, the main cotton variety system of upland cotton in Shandong Province has a single type and insufficient strength. It lacks domestic raw cotton of two grades of fiber length 25 and 31 mm (capable of being blended or blended with 40-60 yarn raw cotton fiber index system, having a main body length more than 30 mm, a specific strength more than 30 cN/tex-1, a micronaire value of 3.7-4.2, and uniformity more than 83%)［2,6］.

Main distribution and farming characteristics of cotton in Shandong province

Since 2005, the cotton production area in Shandong Province has been moderately transferred to three cotton-growing areas, namely the saline-alkali land in northern Shandong, mild secondary saline land of sandy loam soil in the old course of the Yellow River in northwestern Shandong, and high-efficiency two-cropping garlic-cotton intercropping in southwestern Shandong. Specifically, the north of Shandong is the one-cropping area of cotton on the coastal saline-alkali land in the Yellow River Delta, the northwest of Shandong is the old cotton area in the old course of the Yellow River is a mixed cropping area of one-cropping and two-cropping cotton, Southwestern Shandong is a high-efficiency two-cropping area intercropped with garlic and cotton, and central and southern Shandong is distributed with dryland micro-cotton areas. In 2019, cotton planting was mainly distributed in 5 cities and 13 counties in the province; and in 2020, the main planting scale of cotton planting in the province accounted for 25.3% in northern Shandong, 15.2% in northwestern Shandong, 47% in southwestern Shandong, and 12% in other dryland cotton regions［4］.

Guifeng WANG et al. Research and Development of New High-quality Short-season Cotton Varieties and the Industrial Application of High Efficiency Technologies in Shandong Province

Brief analysis of cotton planting cost and benefit in Shandong Province

In recent years, due to the promotion of light and simplified green technology, the cost of cotton planting has decreased. However, the production cost of cotton in the one-cropping area of the province is generally still 33 000-39 000 hm2 (including land cost), in which labor cost is 13 500-15 000 yuan/hm2. The sales income of cotton planting is generally 23 400 yuan/hm2. The mechanized operation rate of cotton production is 48%-50%, and the machine-picked cotton area is 0.4%［2,4］.

For the cost of cotton production in the two-cropping area of cotton, due to the relatively high efficiency of garlic and potato production and the high index of multiple cropping of land, the land cost is relatively low, and material costs is relatively reduced. The superposition of the two factors amortizes the cost of cotton planting, and the comprehensive cost of planting cotton is reduced by more than 65% compared with the planting cost of one-cropping cotton planting.

Brief analysis of industrial application of green and high-efficiency technology for short-season cotton

Suitable short-season cotton varieties can avoid the hazards of diseases, pests and weeds in early spring and late autumn seasons, realize filmless planting, and naturally avoid the "white pollution" caused by mulching film. Meanwhile, it can reduce the labor force by 12-15, save more than 70% of agricultural material input, and increase the overall multiple cropping index of the planting industry by more than 160%［5］, providing technical industrial conditions for all mechanized operations and large-scale planting of previous and ensuing crops, thereby promoting the innovation of green and efficient ecological farming systems.

According to the technical research area test of the green, high-quality and high-efficiency cotton creation project in Dongping County and Juye County from 2018 to 2019, the general short-season cotton yield was stable at 3 375-3 750 kg/hm2. Taking the direct-seeding short-season cotton model in Heze City as an example, calculated at 6-7 yuan/kg, the income was 20 250-26 250 yuan, the material cost was about 3 825 yuan, and the net income was 16 425-22 425 yuan; and the yield of maize was 9 000-9 750 kg/hm2, the income calculated at 1.8 yuan/kg in 2019 was 16 200-17 550 yuan, the material cost was about 4 500 yuan, and the net income was 11 700-13 050 yuan. According to the cotton-wheat model, the income was 2 550-9 450 yuan/hm2 more than the wheat-maize model, and the economic benefits were significant.

High-quality short-season cotton variety research and development and efficient industrialized application of techniques is not only the innovation of new green and efficient farming system and technology system, but also the innovation of cotton industry

Short-season cotton has a shorter growth period than mid-maturing spring cotton, and has become a preferred crop for the current farmland rotation system. It has changed the traditional single-cropping structure of cotton, which is adjusted and optimized to a two-cropping system, effectively reducing cotton planting costs, improving the overall efficiency, and upgrading and stabilizing cotton production.

From 2018-2020, the trial and promotion of the industrial application of approved short-season cotton varieties has become a structural industry measure in some cotton areas to maintain a relatively stable cotton planting industry.

In accordance with the development needs of the mechanical intelligent equipment technological structure of modern textile and garment industry, combined with different production efficiency of agricultural grains, economic crops and fodders, we should accelerate the breeding of high-quality short-season cotton varieties with a growth period stable at 100-105 d, excellent fiber index system, and stable genetic traits, which are suitable for the natural ecological elements of the cotton areas in the traditional cotton planting counties in the west of Shandong Province south of 37° North Latitude and the cotton areas in the traditional cotton-planting counties of southern Shandong at the junction with the 4 provinces of Hebei, Shandong, Henan and Anhui, and are sown before June 5 and harvested in a concentrated manner before September 25［2,7］, so as to establish a new green, high-efficiency and high-quality farming system (planting structure and land-improving system), build a mechanized and large-scale regional layout of supporting crop systems, improve the overall efficiency of agricultural production structure, and coordinate the optimal path of grain, economic crop and fodder industries.

Promotion of the Industrial Technology Integration Route of New High-quality Short-season Cotton Variety Research and Development Background and High-efficiency Technology Industrialization Application

The short-season cotton growing countries and regions in the world mainly include the United States, the five Central Asian countries (Uzbekistan), India, Egypt, Argentina, and the cotton area in northern China. The United States and Egypt plant short-season cotton varieties to reduce or avoid late-stage pests, reduce field management workload, and reduce production costs; and India introduced crop rotation systems in the 1980s, which required the planting of short-season cotton［3］.

China introduced King cotton from the United States through North Korea in 1919. During the "17th Five-Year Plan" period, the former Ministry of Agriculture included short-season cotton breeding in the scientific and technological research plan, and introduced early-maturing cotton materials from the United States, France, Argentina and the former Soviet Union, and selected early-maturing short-season cotton varieties Zhongmiansuo No.10 and Lumian No.10.

From the late 1980s to the 1990s, the wheat-cotton intercropping model was promoted in Heze and Liaocheng, Shandong Province (mainly transplanting cotton seedlings to reserved wheat rows)［4-5］. At that time, cotton varieties had low fiber quality, long growth period (about 120 to 125 d), poor early maturity, large investment in cotton seedling cultivation infrastructure, large labor force, large inter-year differences, etc., and the promotion effect is not great.

The short-season cotton varieties currently produced and promoted have scattered cotton planting areas, multiple planted varieties and serious degradation. In ecological regions, the fiber indexes including specific strength, length, fineness and maturity coordination and consistency are poor, and the fiber quality of the main varieties is homogenized in the middle and low ends, with specific strength in the range of 28-29 cN/tex, average length basically in the range of 27-29 mm, and Micronaire in the range of 4.1-4.8. The ecological type of cotton fiber is highly heterogeneous, and the quality of the finished yarn is significantly lower than that of imported cotton and Xinjiang cotton.

After 2012, Cotton Research Institute of Chinese Academy of Agricultural Sciences, Shandong Academy of Agricultural Sciences, and Dezhou Academy of Agricultural Sciences have successively bred short-season cotton varieties (lines) with stable early-maturing property, high quality, and stable yield, and developed the technical system of double-cropping varieties with crops such as garlic, potato and fodder green manure.

The research and development of high-quality short-season cotton is guided by the demand for the quality structure of raw cotton in the local cotton textile industry, and should scientifically determine the selection and breeding objectives of varieties (lines), which are in line with the direct seeding manner in traditional cotton-growing ecological regions following garlic (wheat, potato, rape, fodder green manure and other crops). We should reasonably adjust the "grain, economic crop and feed" ternary industrial product structure to optimize the regional layout, innovate and improve the technical standard system for cotton seed breeding and improved seed industrialization, summarize production technical regulations, and enhance the integration of the primary, secondary and tertiary industries of cotton.

High-quality short-season cotton variety research and development and technical configuration focus

Based on the lack of excellent germplasm resources, narrow and weak parent genetic basis, late growth and late maturity, low yield, unstable fiber quality and large inter-annual variability in current short-season cotton, according to the current situation of the planting structure of cotton, grains, economic crops and feed and green manure crops in the ecologically suitable cotton areas and sub-suitable cotton areas in the province, it is necessary to scientifically determine the short-season cotton high-quality breeding goal and technology breakthrough key bottlenecks, and build a new type of green and efficient two-cropping farming system［3,8］.

System screening and optimization of cotton germplasm materials

Cotton variety improvement and material innovation and selection can be carried out through the cloning and mining of excellent cotton germplasm genes and the combination of biotechnology with conventional breeding. We can extensively collect domestic and foreign germplasm resources with early or extra early maturity, high quality, and stable stress resistance, use them to select genetic parent materials that develop faster from flowering to boll opening by multi-parental hybridization and fixed-plant hybridization, multiple cross, modified backcross method, distant hybridization, disease nursery screening, and Hainan generation adding  (including multi-site experiment, shuttle breeding) combined with multi-site ecological identification while paying attention to the full use of hybridization technology and the combination of hybrid parent material superiority［9-10］, and aggregate dominant traits with high-quality short-season cotton varieties (lines), thereby cultivating new high-quality short-season cotton varieties (lines) suitable for reasonable rotation of cotton in a manner of "grains, economic crops and fodder".

Specific indicators are as follows: growth period 100-105 d, fiber quality length and specific strength double "30" or more, uniformity more than 83.5%, micronaire value less than 4.6, yield 5% higher than the local current short-season cotton varieties, stable early maturing trait without senilism, and being suitable for spinning raw cotton fiber varieties with more than 40 yarns［3-4］.  The obtained cotton germplasm materials be able to effectively coordinate the problems of lack of short-season cotton germplasm resources, narrow parental genetic materials, late growth and late maturity, low yield, unstable fiber quality and large inter-annual changes in the expression of environmental stress［8,11］.

Research on the technical supporting system matched with ecological production of short-season cotton lines (species)

According to the process of breeding new short-season cotton lines (seeds), we should carry out the classification and integration of green simplified key planting techniques of short-season cotton direct-seeding planting methods for stable yield and high quality, and experiment with different sowing dates, densities, single cropping or interaction effects of different crops, fertilizer and water management, chemical control, mechanized operations and other basic agronomic technology standards and production procedure configurations. According to the analysis of biomass dry matter and technical and economic yield quality, soil nutrient structure and organic matter［2,7］ (specifically including changes in humic acid composition, soil enzyme activity, etc.), we should summarize the optimal farming system model, and explore and improve local high-quality short-season cotton original seeds and improved seed breeding technology standard system (production technology regulations). It is summarized through systematic experiments that a technical standard system for late-spring direct-seeding breeding of high-quality short-season cotton varieties in the cotton-suitable areas of northern Shandong should be established to ensure the healthy seed rate and avoid foreign cross-pollination of cotton.

Research on the key technology integration and industrial innovation technology of high-quality short-season cotton research and development

It is necessary to study garlic and potato suitable for planting in different ecological regions and wheat post-harvest stubble and direct seeding of short-season cotton in the geographical marginal counties of southern Shandong province south of 37° North Latitude, and to study the key technologies of stable yield and increase, high quality, green simplification and mechanization operation supporting technologies of feed green fertilizer crop rotated after cotton planting in northern Shandong province. We can summarize and establish the most suitable stubble crop varieties, suitable sowing time, planting high density, high light efficiency population structure, water and fertilizer simplification, green prevention and control of plant diseases, insects and grass key technologies, etc., and form the green, efficient and high-quality planting system specification of "cotton and garlic (wheat, potato, rape, feed green fertilizer)" that can be copied and promoted.

Promoting the Research and Development of New High-quality Short-season Cotton Varieties and the Construction of a Technology Industrial System for the Industrial Application of High-efficiency Technologies

Research on ecological regions for industrial application pilot demonstration promotion of high-efficiency technologies of high-quality short-season cotton

According to experiments in the 1980s and the past ten years, as well as research on wheat and cotton varieties and cultivation techniques, the wheat and cotton double-cropping farming mode is more suitable in cotton areas with abundant solar and hot water resources.

Basic ecological conditions of double-cropping cotton area

First of all, it must have a certain calorie basis. Wheat and mid-maturing cotton varieties are double-cropped a year, requiring active accumulated temperature≥0℃ of 5 000 ℃ and active accumulated temperature≥15 ℃ of 3 900 ℃.

According to literature research, in the area south of 38° North Latitude (that is, roughly the south of Shijiazhuang-Dezhou), its heat can meet the basic heat condition of double cropping a year［3,8］.

Secondly, more complete irrigation and watering facilities are required. According to the physiological development characteristics of wheat and cotton crops, the water consumption of wheat and cotton in a double cropping system is 900 mm.

A high foundation of soil fertility is also required. For wheat-cotton intercropping, it requires soil organic matter above 0.8%, total nitrogen content above 0.8 g/kg, available phosphorus content above 15 mg/kg, and available potassium content above 100 mg/kg, and loam and light loam is suitable.

Eco-efficient allocation of regional industrial structure system for the industrial application of high-efficiency technologies of high-quality short-season cotton

In recent years, Shandong Province has cultivated an area of about 220 000 hm2 of garlic, about 140 000 hm2 of potato, and about 30 000 hm2 of rape. Shandong Province has dry farming land south of 37° North Latitude and suitable area of early-maturing cotton with abundant solar and hot water resources on the border of Shandong, Henan, Jiangsu and Anhui, and the development potential of agricultural characteristic industries is obvious.

The green and efficient cultivation system mode of the formation of new varieties of high-quality short-season cotton was adopted as the industrial path for the adjustment of planting structure and optimization of traditional cotton planting areas. For the salt and alkali land cotton area in northern Shandong, the cultivation mode of Spring cotton of Northern Shandong was changed to one ripe one year, and the green fertilizer industry mode suitable for direct-seeding of high-quality short-season cotton in late spring with continuous cropping of triticale and oat was tested. A 120 000 hm2 of green, high-efficiency and high-quality special saline-alkali cotton industrial belt with capacity advantage was constructed. We can realize the post-harvest direction seeding of the provinces specialty crops of garlic, potato, and rape, experiment to promote the high-quality short-season cotton industry model after the harvest of wheat in western Shandong and southern Shandong south of 37° North Latitude, and guide the upgrading of the green, high-quality and high-efficiency planting production system in the traditional old cotton areas of Shandong Province.

It is necessary to promote the "order-based" industrial model of integrating "ginning factory+new large cotton planting group (cotton farmers cooperative)+textile processing enterprise" whole-industry-chain "cultivation, planting, management, harvesting, ginning, spinning" with cotton primary, secondary and tertiary industries, so as to enhance the competitiveness of Shandong cotton industrys characteristic industries.

Promoting the Development of High-quality Short-season Cotton Industry and the Research and Development of Ecological Products

Cotton is a basic economic crop with the green industrial characteristics of plant fiber, high-protein feed materials and edible oils.

In addition to the industrial characteristics of green raw cotton fiber, the cotton kernel contains more than 35% of high-quality oil and 37%-40% of protein with complete amino acid content. In terms of planting industry structure adjustment and optimization and intensive utilization of cultivated land, it has a structural substitution effect for the niche planting of soybean, peanut, and forage corn planting area units and improves the niche efficiency.

Researching breakthroughs in the basic research theory of intensive and deep processing of short-season cotton feed protein and edible vegetable oils and comprehensively researching on the use of cottonseed protein and oil industrialization technology integration innovation is an important direction to expand the multi-functional ecological application of the cotton industry［4,13］.

Combining with Basic and Applied Technology Research to Make Breakthroughs in Major Technological Innovations

According to related research, traits of short-season cotton yield and fiber quality are quantitative inheritance controlled by polygenes, and also restricted and affected by many other factors. The yield traits and yield component traits of short-season cotton varieties, including ginning outturn, boll weight, and boll number inheritance are dominated by dominant effects and interaction effects between dominant and environment, as well as the existing additive effect and the interaction effect between the additive and the environment［8,10］. Attention should be paid to the research and breeding of short-season cotton field agronomic cultivation and farming technology integration system.

Systematically studying short-season cottons main rotation (such as garlic, rape, wheat, potato) crops and fodder green manure crops can feed in suitable harvest planting ecological environment conditions of direct seeding

It is necessary to establish a technological optimization approach of new cotton varieties and "grains, economic crops and fodder" rotation advantage planting regional planning and layout, and achieve grain-cotton, cotton-economic crop and cotton-fodder double-cropping industrial model innovation with high-quality short-season cotton as a technological breakthrough［14］. In summary, we should form a green, high-quality and high-efficiency farming technology system.

Study the key technologies to solve the problems of late growth and late maturity, low yield, and inter-annual and inter-season instability of fiber quality in short-season cotton

Systematic experiments should be carried out to summarize the supporting agronomic measures for improving the integration of comprehensive technologies, matched with planting density, coupling of fertilizer and water, chemical regulation and promotion, and efficient use of light and heat resources.

Organizational Guarantee for Promoting the Research and Development of New Varieties of High-quality Short-season Cotton and the Industrial Application of High-efficiency Technologies

The research and development of high-quality short-season cotton and the industrial application of high-efficiency technologies are a major technological innovation integration and industrial innovation system technology project for the green, high-efficiency and high-quality development and transformation of Shandong cotton planting industry, and we should establish a major technological innovation coordination mechanism led by the cotton industry technology public management service organization in the province that closely integrates production, education and research and takes the modern textile industry technology innovation platform as the mainstay［2,15］.

In terms of demonstration application and promotion, we will give full play to the organizational advantages of the public management service system of cotton production technologies in Shandong Province, and establish a province, city and county three-level high-efficiency technology industrialization application "point-to-surface integration linear promotion" experimental demonstration application organization efficiency model.

It is necessary to keep track of technological progress closely. We should systemically carry out experimental contrast of short-season cotton varieties (lines) directly seeded after harvesting of rotational crops, test germplasm screening purity-conservation technologies, and establish supporting high-efficiency technology integrated ecological experimental research, thereby gradually establishing a basic technical formula.

We should actively research and explore the construction of the mechanisms and methods for developing and promoting the effective scale regionalization of Shandongs high-quality green production of cotton through green finance［16］, and form an industrial organization mechanism of green finance supporting the sustainable development of high-quality cotton production.

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