Research On The Root Rapid Growth Technology Of Grafted Cucumber Seedlings

Cucumber is one of the important edible vegetables in people’s daily life, which contains a large number of human essential vitamins. Cucumber root is the important organs to absorb water, inorganic salt and a small amount of organic material, synthetize essential nutrients of the crops growth and development. The growth and development of cucumber root system directly affects the yield of the cucumber and the growth of the aboveground parts. To strengthen the research on cucumber root has important significance for increasing crop yield and achieving high production and high efficiency agriculture. Grafting has widely been used in crop breeding. However, the current research of domestic and foreign scholars on the grafted seedlings has focused on the stems, leaves and fruits etc, rarely involved in root growth. So this paper conducted a systematic study on the grafted cucumber seedlings(cucumber scion, pumpkin rootstock) root in four stages.The first stage: take cucumber seedlings as the research object, with three kinds of grafting experiments(double root cut grafting, cottage grafting and by connection grafting),compared the index of grafting time, survival rate, root length, root number, root vigor, found that: with double root cut grafting, the grafted seedlings had high grafting efficiency, short grafting test time, high survival rate of grafted seedlings, grafting significantly increased cucumber seeding root activity,and root activity enhanced significantly with double root cut grafting, root grew faster and developed better. So in the latter stages the cucumber seedings are grafted by the method of double root cut.The second stage: respectively took soil culture and aerosol culture methods as cucumber grafted seedlings cultivation. Compared the time of grafted seedlings’ primary roots, root length, root volume, root number, root weight, root vigor and bleeding sap volume, the results indicate that: compared with soil culture rooting method, using fog culture method the growth of grafted cucumber seedlings is two days in advance, the rooting rate increases 3.78%, the root vigor increases 31%, the root length, root number, root volume and root weight respectively are 1.44, 1.49, 2.38 and 1.72 times of soil culture method, the bleeding sap volume is 1.52 times of soil culture method. Therefore, compared with soil culture rooting method, using fog culture rooting method the grafted cucumber seedlings’ root grows earlier,the root vigor is more powerful, the root grows more rapidly, all these is more conductive to grafted cucumber seedlings’ growth and development.The third stage: took aeroponic culture rooting method do experiments of climate environment orthogonal experiment and nutrient solution culture environment orthogonalexperiment, used the results of root composite indicator and root activity index analysis the environmental factors effect order and the optimal climate control environment. The results show that: the effect order of climatic factors on the growth of grafted seedlings was:temperature > light > humidity. The optimal climate control environment factors: climate temperature 25 ℃, humidity 80%, light 6000 Lux. The effect order of nutrient solution environmental factors on the growth of grafted seedlings was: pH>EC> spraying time >planting spacing. The optimal nutrient solution environmental factors: the planting spacing12 cm, pH 6, EC 2.5mS/cm, spray time 30s/5min.The fourth stage: took single factor test and multi factor orthogonal experiment to study high temperature and low temperature stress of the root system of grafted seedlings, the rusuts show that: high and low temperature stress on the relative conductivity of grafting root and root activity influenced highly significant, which is higher effect than cultivation mode and grafting varieties; Under high temperature stress, the root length of grafted seedlings increased,but the root fresh weight, root volume, root diameter and root number decreased, root relative conductivity increased, root vigor dropped, grafted seedling’s root apparent over growth phenomenon; Under low temperature stress, the root length, root fresh weight, root volume,root diameter and root number were significantly decreased, root relative conductivity increased, root vigor drops, root of grafted seedlings developed slowly. The result suggested that high and low temperature stress affect the grafted seedling’s root normal growth,especially the high temperature stress.