Effects Of Different Storage Methods On Seed Quality Of Juglans Sigillata Dode

Juglans sigillata Dode is a kind of important grain and oil woody plant of Chinese which contains economic, ecological and social benefits, and plays an important role in the process of poverty alleviation and development of ecological construction in mountainous area. It is one of the four biggest nuts in the world, known as “brain gold”, further more, it has great medical, industrial and ecological value. The walnut production of China ranks No.1 in the world, however, face such a huge production, the study of seed storage is behind the yield, caused 12% losses per year. Nowadays, Guizhou province is consucting and developing walnut industry actively, and it asks a large number of seeds to cultivate rootstocks for seedling grafting. Since florescence of walnut is between March to April, while it often appears spring cold in Guihzou, and it has an adverse effect on flower bud differentiation, finally, it caused walnut trees bear no nut. Seed is the initial body of plant and storage the genetic informations, it is the most basic means of agricultural production, its quality is the key factor to agricultural production, and to obtain a sufficient number of eligible seeds, it not only needs proper field management, but also scientific storage method.In addition, forestry production is seasonal, therefore, research and find a right storage method became an urgency to disaster preparedness, avoid huge economic losses caused by improper storage, and provide adequate standard walnut rootstock, and to provide scientific basis for the development of seed storage of Guizhou walnut industry.The paper selceted three different thickness of walnut(Juglans sigillata Dode) shell as test materials: the thin(⑤, 0.85~0.87mm), the moderate(④, 1.28~1.34mm) and the thick(⑦, 1.70~1.90mm) to launch dry storage and wet storage respectively. Wet storage choose stacking sand-hidden; dry storage is divided into normal temperature storage and low temperature storage(0℃, 10℃), and combinate with differrent packaging materials(without packaging, polyethylene plastic film, aluminum film) to set the different storage conditions, and determin the storage substance content, physiological and biochemical indexes and seed viability. Through the study of effects of different storage conditions on the quality of walnut, the change of walnut quality with storage time, the wet comparison between storage and dry storage, to explore the optimum conditions of walnut storage.The main results are as follows:(1) With the extension of storage time, the vigor indexes of walnut under different storage conditions showed different change, but the tendencies were similar: crude fat content, soluble sugars and soluble protein content decreased with the time; SOD activity icreased, POD activity decreased with the time, and CAT activity decreased in 0~270d storage, 270~360d increased slightly; the content of MDA increased with the time; when it comes to seed viability, it maintained at above 90% after 90 d storage, after 180 d it still keeped at a high level, but as the time goes by, seed viability decline is more and more big at same time interval, after 360 d, 1,8,9 treatments decrease sharply, down to about 10%, 4 and 6 treatments maintained at more than 60%, 1,2,3,5 treatment maintained at above 80%. The time of storage at room temperature should shoter than 180 d.(2) Three factors had significant effects on moistrue content; crude fat content affected by temperature and shell thickness mainly; soluble sugars content were affected by temperature and shell thickness mainly; soluble protein content affected by temperature; SOD activity was affected by temperature mainly; three factors affected CAT activeity; POD activity affected by temperature and packaging mainly; MDA content was affected by emperature and shell thickness; the factor influence seed activity primarily were temperature and shell thickness, but in the first 90 d, the difference of 9 treaments were similar to each other. In general, temperature had a significant influence on every vigor index, within 360 d of storage time, shell thickness had no significant effect on the activity of POD, and packaging had no significant effect on crude fat content. According to the analysis of all vigor indexes, A1B3C3( 0℃, aluminum film, 1.70~1.90 mm, 3) is the best treatmnet of 9 treatments. Temperature and packaging materials are external environmental factors, and shell thickness is one of the inherent properties of walnut, therefore, it’s necessary not only to provide suitable storage conditoins, but also select sort of walnut. But when there’s no sort to select, A1B3C2( 0℃, aluminum film, 0.85~0.87mm) recommend for ④ walnut, A1B3C1( 0℃, aluminum film, 1.28~1.34mm) recommended for ⑤ walnut, A1B3C3( 0℃, aluminum film, 1.70~1.90 mm, 3) recommend for ⑦ walnut, but A1B3C2, A1B3C1 are not in the orthogonal table, they need verificate before utilize. On the other hand, the seed activity of 4, 5, 6 teatment of 360 d under 10℃were 66.7%, 88.3% and 70.0% respectively. Compare to 0℃, set 10℃ as the storage temperature can save more energy and money.(3) Comprise dry storage and wet storage, ④, ⑤, ⑦ walnuts’ 2,1,3 treatment is the optimal combination, but there’s no significant between the crude fat, soluble sugar, soluble protein, MDA content, CAT activity and POD activity, of 2 and 4s, 1 and 5s, 3 and 3s, and the seed activity were similar to each other, all abovet 90%.