抗旱小麦品种根系垂直分布和根尖特征分析研究

A Analytical Study on the Vertical Distribution of Root and the Characteristics Root Tips of Drought-Risistant Wheat Varieties

为明确抗旱小麦品种根系的垂直分布和根尖特征,以抗旱品种新麦39、洛旱22和干旱敏感周麦36、郑麦369为材料,采用柱栽法,在雨养和高产灌溉两种水分条件下比较分析了两类品种产量、根系形态特征的差异。结果表明,雨养条件下,抗旱品种籽粒产量高于干旱敏感品种,而高产灌溉条件下产量表现则相反。两类品种根长度、根干重和根体积具有显著差异,抗旱品种在表层(0~20 cm)、中层(20~40 cm)和深层(40~60 cm)土壤中的根长度、根干重和根体积均高于干旱敏感品种;雨养条件下表层和中层土壤中的根长度、根干重和根体积均显著低于高产灌溉条件,而在深层土壤中高于高产灌溉条件。不同土层中抗旱品种的根尖数和根尖长度均高于干旱敏感品种,而根尖直径则小于干旱敏感品种,其中高产灌溉条件下,抗旱品种在表层土壤中的根尖长度和根尖数分别较干旱敏感品种分别高17.2%和24.11%,根尖直径低14.2%,差异均达显著水平。与高产灌溉条件相比,雨养条件下不同土层中的根尖长度和根尖直径均降低,表层土壤中的根尖数减少,而中层和深层的根尖数则增多。这说明抗旱品种的根系生长发育状况优于干旱敏感品种,有助于适应干旱胁迫和增加产量。

In order to determine the vertical root distribution and root tip characteristics of drought-resistant wheat variety,the study was carried out under two water conditions of rain fed and high yield irrigation with two drought-resistant wheat varieties,Xinmai 39,and Luohan 22,and two drought-sensitive varieties,Zhoumai 36,and Zhengmai 369,as experimental materials.The yield and root morphologic indexes of the two groups of wheat varieties were compared under different water conditions.The results showed that the grain yield of drought-resistant varieties was higher than that of drought-sensitive varieties under rain-fed conditions,but the yield performance was opposite under high-yield irrigation conditions.The root length,dry weight and volume of the two groups were significantly different.The drought-resistant varieties had higher values for length,dry weight and volume of the root than the drought-sensitive varieties did in the surface(0-20 cm),middle(20-40 cm)and deep(40-60 cm)soil layers.The root length,dry weight and volume of surface and middle soil layers under rain fed conditions were significantly lower than those under high yield irrigation conditions,but their performances were opposite in deep soil layer.The root tip number and root tip length of drought-resistant varieties in different soil layers were higher than that of drought-sensitive varieties,while the root tip diameter of the former was smaller than that of the latter.Under high-yield irrigation conditions,the root tip length and root tip numbers of drought-resistant varieties in surface soil layer were 17.2%and 24.11%higher,respectively,and the root tip diameter was 14.2%significantly lower than those of drought-sensitive varieties.Compared with high yield irrigation treatment,the root tip length and diameter of rain fed treatment in different soil layers decreased,and the root tip numbers in surface soil layer decreased,but the root tip number in middle and deep soil layers increased.It was suggested that the root growth and development of drought-resistant wheat varieties was better than that of drought sensitive varietives,which was helpful to adapt to drought stress and increased yield.