| Water resources in Northwest of China is only one twelfth of countrywide gross, water shortage has obviously restricted production of industry and agriculture and leaded to serious erosion of water and soil ,but at the same time phenomena of waste water widely exist in agricultural production. It is reported that in china irrigative water use efficiency is only 0.4 ,and that water use efficiency of crops is 1 kg/m3; and is only half of developed country, thus it can be seen that the key of saving agricultural use water is to how to increase crops use water efficiency .Maize is one of spring sowing and summer replanting crops in northwest area ,research how to decrease luxurious transpiration is a hotspot problem, a saving water and high yield variety possess obvious economical advantage at absorbing and consuming water and yield , this rests variety character ,it is reported that diversity of water use efficiency of variety can reach to 30%~100%, and is a inherited character, the analyze of Physiological mechanism of diversity of water use efficiency of maize variety can provide Physiological foundation that people choose maize variety of saving water and high water use efficiency in arid and semiarid area.Based on pot ^ water and farm experiments, the mainly results showed :1. Under middle water stress ,water use efficiency of 12 varieties Based on biomass was obviously higher than full supplied water condition at 4 stages,2. Consuming water > biomass accumulation and water use efficiency of 12 varieties existed obvious diversity , zhendan 958 xVedan 13 and shandan 911 belonged to high water use efficiency > high yield and consuming water varieties ,zhongdan 2 belonged to high water use efficiency ^ mid 梱ield and mid æ¢'onsuming water variety, nongda 60 > shandan 902 belonged to high water use efficiency -. mid 梱ield and saving water varieties; hudan 1 > hudan 4^ yedan 19 and shendan 10 belonged to mid water use efficiency s mid梱ield and saving water varieties;shandan 9 and danyu 13 belonged to low water use efficiency > low梑iomass and saving water varieties ?3. The relation of Gs ., Pn and Tr of 12 varieties was linear , the correlativity between Gs and Tr was higher than the correlativity between Gs and Pn, the influence of water stress to Tr was bigger than to Pn ,under middle water stress, the descendant range of shandan 911' Pn and Tr was the biggest of all varieties, the descent of Tr was middle ,so descant of its rising efficiency was the most biggest of all; and that descant of nongda 60'Pn was the least of all, but of its Tr was the most of all, so descant of its rising efficiency was the least, the behave of zhongdan 2 was middle.4. Amount and length of leaf epidermal hair and bristle were nongda 60 > zhongdan 2 shandan 911;through the analyze to stoma shape ,we found that guard cell of nongda 60 > shandan 911 and zhongdan 2; stoma amount of 3 varieties were not obviously different, but stoma opening extent were different , under mid water stress, stoma opening extent of shandan 911 was obviously bigger than nongda 60 and zhongdan 2,stoma adjustment ability of nongda 60 and zhong dan 2 obviously was more excellent than shandan 911 ?5. On the condition of normal water, distinguish of RT of 3 varieties was not obvious, Under middle water stress ,root weight was nongda 60 > zhongdan 2 > shandan 911,the hydraulic conductivity of root was that nongda 60 increased 54.64%,zhongdan 2 ^ shandan 911 respectively declined 50.94%,63.00%; the arid adaptation ability of root of shandan 911 was lower than zhongdan 2 and nongda 60 ?6. the osmosis adjust capacity was shandan 911 > zhongdan 2 > nongda 60, the excised leaf water retention capability was shandan911 > nongda 60 > zhongdan 2 =7. Based on farm experiments .the results showed: yield diversity of varieties were obvious , yield of shendan 10 was the highest in all varieties, adjustment ability was the strongest in all varieties, secondly was nongda 60> shan... |
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