Study On Industry Key Technique Of Winter Flax In Red Soil Zone Of Southern China

Flax(Linum usittatissiumum L.),an annual herbal fibrous plant in Linum,is one of the three major fibre crops and the five major oil crops in the world.There are three flax ecotypes, including cultivars for fibre(generally called flax),oil and both(also called benne).Flax is a long-day-plant which is fond of mild and humid environment,and distribute mainly in the high latitude countries and areas from northern latitude 39 to 53 degree in the world.To address the important theoretic problems on flax transplant from northern China area to southern China area in the winter,and the technical problems on planting as well as degumming during fiber-processing to yield higher fibre output and quality in the red soil zone of southern China,experiments were conducted to study the physiological characteristics of growth and development,ecological adaptability and its physiological mechanism,the key cultivation technique for high output and quality,the phloem peeling machine and degumming technique as well in this paper.The results are as follows:1.The physiological characteristics of flax growth in the winter in red soil zone of southern ChinaIt was found that the growth duration of flax planted in the winter(winter flax) in southern China is more than 80 days longer than flax planted in the summer(summer flax) in the native area through the dynamic observation of the change of root's weight,volume, surface area,absorbing area and also the oxidative activity of flax root system.It was also found that the absorption area of flax root reduced rapidly and the oxidative activity almost came down to zero in lower temperature stage of middle January,thus forms two rapid growth peaks during the whole growth duration,that is winter and spring growth peak for winter flax in red soil zone of southern china.The rules of flax stem growth and phloem fibre development were achieved by the systemic observation of stem height,size,weight,and the microscopic observation of the morphogenesis of phloem cell in middle part of flax stem. Leaf differentiation and population photosynthesis characteristics of flax and the dynamics of the absorption,distribution and accumulation of main nutritious element(mineral element), the flax bud beating,flower setting and seeds development were also discussed in this paper. The main reasons of seed-setting failure after flowering was found for winter flax in red soil zone of southern China and thus new culture mode for planting flax in winter of these area was proposed,that is to product fibre and seed in separate areas.2.The ecological adaptability of winter flax and its physiological mechanism in red soil zone of southern ChinaThe adaptability of flax to winter ecological factors and the best plant season in red soil zone of southern China was found by different planting time experiment in whole year.The tolerance of flax to low temperature during the early and middle stage of whole growth duration was tested under the stress of low temperature,it was found that the flax seed could not sprout out of the soil when the temperature came down to 0℃during the early stage of white-embryo and radicle development,and the flax seedlings would be pulled out gradually by the icicle formed on soil surface and die.But young seedling flax can bear short period of low temperature of-5℃for 12 hrs.This solves the surviving problem of transplant flax to the red soil hill zone of southern China in winter theoretically.The adaptability of flax to a wide spectrum of light length is rather high.It was found that flax was able to bear bud and flowering normally under the light length of 9～18 hrs per day,leading to revise the theory that short-day-light will cause fibre lignification.It was showed that flax had stronger tolerance to water stress,and could not only sustain for about 45 days under the water stress of 55%field water,but also grows normally under soil submergence at lower temperature and some degree of water leakage.Flax was also found to be strongly adaptable to red soil of southern China,the Quaternary red soil is the best suitable soil for flax growth,but limestone soil with high pH and purple soil with bad water maintenance is not suitable for the growth of winter flax.3.Key techniques for high output and quality as well as economic efficiency for winter flax in red soil zone of southern ChinaWell-bred flax cultivars of "ALALINA and FANNI" were selected from many international and internal good cultivars.These two cultivars are suitable for growth in the red soil zone of southern China in winter,and could match better with the two- season- rice culture system.To overcome the main problem of soils in the red soil zone of southern China which are viscid,acidic,arid,stuffy,barren,and the paddy soil hard to plough and smash,it is suggested that the sowing time is from end of October to early of November,the best dosage of seeds is 90.0 kg/hm~2,and sowing technique should focused on "root digging, shallow ploughing,furrow irrigation" to raise the flax yield and fibre quality. The best fertilization measures are suggested that the dosage of nitrogen should be controlled and potassium enhanced,and fertilizer should be used mainly in winter rather than in spring.The best dosage of nitrogen is 75.0Kg/hm~2 and the best fertilization combination is " 60%in sowing stage + 40%in seedling stage ",the dosage of potassium and phosphorus are 37.5～75.0 Kg/hm~2 and 22.5 Kg/hm~2 separately.Safety and high efficiency for winter flax in red soil zone of southern China is emphasized for pesticide combination and herbicide usage,that is,Du'er in germination stage and Gaoxiao Gaicaoneng in stem and leaf development stage.And new lodge prevention technique using chemical to kill pollen and strengthen the stem are also suggested according to the main factors for lodge of winter flax in red soil zone of southern China.4.Phloem peeling machine and degumming technique for raw flax fibre in red soil zone of southern ChinaBased on the physical and mechanical characteristics differences between fresh tegument and stalk,bast fibre cell and nearby cell,a new type of combined peeling and washing machine was designed for the first time in the world.At present the machine is mini type and oriented in house use.New set of degurnming technique,which including chemical degumming to raw flax bast fibre(boiling in alkali solution),physical degumming(boiling and pressing under high presure),fermental degumming(retting in warm natural microbe solution),was also developed according to the basic characteristics of raw flax.In this new technique,the traditional long-used technique all over the world of raw stem harvest is changed to the technique of raw phloem harvest,so as to change the traditional craft lasting thousands of years of history,and thoroughly resolve a serial problems of long-distance transportation,flax mould and rotten,complex craft,lower efficiency and bad workshop environment,which are the bottle neck for sustainable and high efficiency development of flax industry.