| Jingyuan County of Baiyin is the main dry sandy melon producing area in our province.Due to the drought and lack of local climate,the surface evaporation is strong,and the necessary irrigation facilities are lacking.The output is severely restricted by water.This experiment is based on the selection of 2 seed watermelons(Heifeng 1 & JingYuan daban)and 2 watermelons(Jincheng & Jinhua)which are widely cultivated locally as materials,measured 8 photosynthetic physiological indexes and 6 physiological and biochemical indexes.The results were analyzed by variance analysis,correlation analysis,membership function value analysis,grey correlation analysis and principal component analysis in order to sort the drought resistance of 4 kinds of melons.Making full use of local climate resources and improve crop yield and farmers' income from the angle of drought resistance,it provides a reference for rational selection and planting in the local area.The results showed that:(1)In the determination of Photosynthetic Diurnal variation,the phenomenon of "photosynthesis midday rest " was found in all 2 seed watermelons.2 types of watermelon in the light saturation point is far larger than 14 of the photosynthetically active radiation,so it can be certainly the two seed watermelons Pn in 14 when the drop is not because the light intensity was higher than light saturation point caused by photoinhibition caused by leaf,but because of the closure of part of stomatal caused;2 Watermelon Cultivars had no obvious "midday rest".(2)The 4 kinds of melons are all positive plants,which can be well performed under strong light.It is suitable for growing areas with strong sunshine.The light saturation point and light compensation point of 2 kinds of watermelon were all higher than those of 2 kinds of seed watermelons,indicating that the watermelon had higher requirement for light intensity,and the requirement of light intensity of seed watermelon was relatively low.(3)It is found that the temperature of each leaf is slightly lower than the air temperature.The analysis shows that this is because in summer high temperature period,transpiration is stronger and its temperature is reduced.Seed watermelon leaf temperature is slightly higher than the watermelon leaf temperature and transpiration can infer watermelon seed watermelon is stronger,the stomatal opening is greater,thetranspiration heat loss more.What's more,the difference between the leaf temperature of the "Jinhua" watermelon and the Test ground's temperature is the biggest,while the "Jingyuan daban" seed watermelon's is the smallest.(4)The analysis of photosynthetic physiological indexes showed the drought resistance of 4 kinds of melon under low light was that : Jingyuan daban > Heifeng1 > Jinhua > Jincheng.In the case of strong radiation,the drought resistance sorting is that: Heifeng 1 > Jingyuan daban > Jinhua > Jincheng.(5)The order of drought resistance of the 4 kinds of Melon under the stress of different concentration of chemical desiccant was as follows: Jingyuan daban >Heifeng 1 > Jinhua > Jincheng.(6)For the 2 seed watermelons,there was a significant change in the index values under 300-500mg/L concentration stress,indicating that the concentration of 2seed watermelons was most obvious to the stress response.While for 2 kinds of watermelons,the most obvious concentration range was slightly lower than that of seed watermelon,about 100-300mg/L.Ethephon is sprayed on the fruits during ripening,and sprayed on the leaves during stress,which should pay attention in the production process. |
PDF Full Text Request