杂交玉米品种黔玉3号耐旱和耐盐能力的鉴定

Identification of Drought and Salt Tolerance of Qianyu 3 (a Hybrid Maize Variety)

分别用不同浓度的PEG-6000和NaCl溶液模拟干旱和盐胁迫,以常规玉米品种农大108为对照,从水分状况、膜伤害、光合速率、渗透势和离子吸收等生理指标对杂交玉米品种黔玉3号幼苗的耐旱和耐盐能力进行了比较和鉴定。结果表明,供试两玉米品种受胁迫后,地上部相对含水量、叶片净光合速率(Pn)和PSⅡ最大光化学效率(Fv/Fm)都降低,叶片相对电解质渗漏率及盐胁迫下植株的Na+/K+值都升高,农大108的变幅大于黔玉3号;叶片渗透势都降低,在盐胁迫下植株SRK,Na值都升高,但农大108的变幅小于黔玉3号。通过上述指标的综合评价表明,黔玉3号的耐旱、耐盐能力大于农大108。

Different concentrations of PEG-6000 and NaCl were used in Nongda 108（CK） and Qianyu 3 to compare the drought and salt tolerance of their seedlings from physiological indexes of water status, cell membrane damage, photosynthetic rate,osmotic potential and ion absorption. The results showed that the aerial relative water content, leaf net photosynthetic rate （Pn） and maximal PS Ⅱ photochemical efficiency（Fv/Fm）of two tested maize varieties all decreased under the both stresses, the leaf relative electrolytic leakage ratio of two tested maize varieties rose under the both stresses, the Na^＋/K^＋ ratio in young seedlings of two tested varieties rose under the salt stress but the variation range of Nongda 108 higher than Qianyu 3, the leaf osmotic potential of both stressed seedlings decreased and the SRK,Na value in young seedlings of two tested varieties rose under the salt stress but the variation range of Nongda 108 lower than Qianyu 3. The drought and salt tolerance of Qianyu 3 is higher than Nongda 108 by evaluating the physiological indexes comprehensively.