Effect Of Seed Size On Cucumber Growth And Development And Its Genetic Analysis

Cucumber is one of the important economic crops to ensure the annual supply of vegetables in China,the demand for cucumber seeds is large.Seed size affects cucumber seed production efficiency.Within a certain range,if the small seed does not affect the growth and yield of cucumber,We can improve cucumber seed production efficiency and reduce production costs by cultivating varieties with smaller seeds.In this experiment,the cucumber variety Xintaimici with extremely significant difference in seed size was used as the material,two kinds of seeds with extreme size were selected for experiment,the effects of seed size on the growth and development of cucumber plants and the yield of fruits and seeds were studied,and the genetic law of seed size of Xintaimici used in this experiment was analyzed.The main results are as follows :(1)The length,width and 1000-grain weight of the two types of seeds used in this experiment were significantly different,but the length-width ratio of the seeds was not different.Therefore,seed length was used to represent seed size in subsequent experiments.(2)In the range of 5.6-8.7 mm seed size,the big and small seeds all germinated after 32 h of germination,and there was no difference in germination rate;there was no difference in radicle length between large and small seeds at 18 h,23 h and 28 h after germination.(3)Under the condition of all seed germination,the plant height,dry weight,fresh weight,root length,root surface area and seedling index of large and small seed seedlings were significantly different before 16 days,the stem thick and root surface area were significantly different before 11 days,and the growth of large seed seedlings was better than that of small seeds,but there was no significant difference in leaf area between large and small seed seedlings.(4)After irrigation with nutrient solution,the difference of root surface area and root volume between large and small seed seedlings disappeared,and the difference time of plant height,stem diameter,dry weight,fresh weight,root length and seedling index was significantly shortened(shortened to 11 d and 7 d).(5)There were no significant differences in plant height,stem diameter,leaf area,leaf number,first female flower position,female flower number,melon length,transverse diameter,single fruit weight and single fruit seed weight between large and small seed plants at flowering and fruiting stages.(6)Genetic analysis showed that the seed size of Xintaimici cucumber used in this experiment was quantitatively inherited,but the variation range of cucumber seed size may be controlled by single gene.In summary,this study found that seed size only affected the early growth and development of cucumber seedlings in the range of 5.6-8.7 mm,moreover,watering nutrient solution can reduce the time of seed size on seedling growth;it does not affect the late growth and development of cucumber plants;it did not affect cucumber growth and yield per plant.It does not affect the weight of single melon seeds.And seed size is affected by genetic law.Therefore,in cucumber breeding,cucumber varieties with small seeds can be cultivated to improve the efficiency of cucumber seed production and reduce the cost of cucumber production.This study showed that the seed production efficiency of small seeds could increase 39.78% of cucumber seed production efficiency compared with large seeds without affecting seed yield.