春季双层膜覆盖对独头蒜形成及品质的影响

摘要

Taking 5 garlic varieties,including Leduzi,Japan garlic,Japan rocambole,Xinjiangzi 2,He-beibaigou,as materials,with single plastic film covering as control,the effects of double -layer film covering (plastic film and small arch shed)for 10 days and 20 days in spring on the formation and quality of single -clove garlic were studied,so as to provide references for gaining the high -yielding and good -quality single -clove garlic.The results showed that the plant height,false stem length,false stem diameter,leaf width,leaf length,pigment content,net photosynthetic rate (Pn)significantly increased,and the single -clove rate,sin-gle head weight and the contents of allicin,VC,soluble protein and soluble sugar were higher under double -layer film covering for 10 days.The growth of garlic was harmed by latter higher temperature under double -layer film covering for 20 days.The single -clove rate of Hebeibaigou was 94.63%,85.23% and 80.12%respectively under the double -layer film covering for 10 and 20 days and single plastic film covering,whichwere all higher than those of the other varieties.The single head weight of Hebeibaigou was 6.82,5.92 and5.52 g respectively under 3 treatments,which were only lower than those of Leduzi.The single head weight ofLeduzi was more than 8 g,but its single -clove rate was less than 30%,so it was not suitable for productionof single -clove garlic in spring.Compared with single plastic film covering,the contents of allicin,VC,soluble protein and soluble sugar in bulbs of Hebeibaigou increased by 12.58%,13.22%,4.35% and 6.88%respectively under double -layer film covering for 10 days.In conclusion,the best variety,which was suitablefor producing single -clove garlic in spring,was Hebeibaigou,and the optimum covering date was for 10 dayswith double -layer film.%以乐都紫皮、日本大蒜、日本小蒜、新疆紫2、河北白沟5个大蒜品种为试验材料，以单独地膜覆盖为对照，研究双层膜（地膜＋小拱棚）覆盖10 d 和20 d 对独头蒜形成及品质的影响，为获得优质高产独头蒜提供参考。结果表明：双层膜覆盖10 d 处理的5个大蒜品种的生长量（株高、假茎长、假茎粗、叶宽及叶长）、色素含量、净光合速率（Pn）明显提高，独头率、单头重及大蒜素、VC、可溶性蛋白、可溶性糖含量也较高；双层膜覆盖20 d 处理后期温度超过大蒜生长最适温度，影响其正常生长。5个大蒜品种中，河北白沟大蒜的独头率在双层膜处理10、20 d 及单独地膜覆盖时均高于其他品种，分别为94．63％、85．23％、80．12％，单头重分别为6．82、5．92、5．52 g，仅低于乐都紫皮。乐都紫皮独头蒜单头重达8 g 以上，但其独头率不足30％，不适于春季播种生产独头蒜。与单独地膜覆盖相比，河北白沟大蒜在双层膜覆盖10 d 时其鳞茎中大蒜素、VC、可溶性蛋白、可溶性糖含量分别提高了12．58％、13．22％、4．35％、6．88％。因此，春播获得独头蒜应选择的最优品种是河北白沟大蒜，最佳双层膜覆盖时间为10 d。