盐胁迫对热带水稻生长、生理生化特性及产量构成的影响

Effects of Salt Stress on the Growth,Physiological and Biochemical Indices Characteristics and Yield Composition of Tropical Rice

我国土壤盐渍化问题日趋严重,水稻是盐渍化土地改良的首选粮食作物,而盐胁迫是影响水稻生长和产量的主要非生物胁迫之一。为全面深入了解盐胁迫对水稻的影响,以31份不同耐盐性的热带水稻品种(系)为试验材料,采用幼苗期培养箱水培法和全生育期盆栽土培法开展试验,研究0 NaCl(CK)、0.3%NaCl和0.6%NaCl对热带水稻生长、生理生化特性及产量构成的影响。结果表明:(1)盐胁迫抑制了热带水稻幼苗和根系的生长。其中苗高和根数随NaCl浓度的升高而显著降低;0.3%NaCl和0.6%NaCl处理的根长显著低于CK处理;0.6%NaCl处理的苗鲜重显著低于CK和0.3%NaCl处理。(2)盐胁迫使热带水稻叶片的叶绿素积累降低,0.3%NaCl和0.6%NaCl处理的叶绿素a、叶绿素b及类胡萝卜素含量均显著低于CK处理;脯氨酸(Pro)、丙二醛(MDA)及Na^(+)积累增加,0.6%NaCl处理的Pro含量、MDA含量及Na^(+)含量均显著高于CK和0.3%NaCl处理;K^(+)积累下降,0.3%NaCl和0.6%NaCl处理的K^(+)含量显著低于CK处理。(3)盐胁迫下,热带水稻的分蘖数、穗数、穗长、穗粒数、千粒重及单株产量均随NaCl浓度的升高而显著降低。

The problem of soil salinization in my country is becoming more and more serious.Rice is the preferred food crop for the improvement of salinized land,but salt stress is one of the main abiotic stresses that influence the growth and yield of rice.In order to fully understand the effect of salt stress on the rice,31 varieties(lines)of tropical rice with differ-ent salt tolerance were used as experimental materials,and experiments were carried out by hydroponics in seedling stage incubator and potted soil cultivation method in the whole growth period,to study the effects of 0 NaCl(CK),0.3%NaCl and 0.6%NaCl on the growth,physiological and biochemical characteristics,and yield composition of tropical rice.The result showed that:(1)The seedlings and roots growth of tropical rice were inhibited under salt stress.The seedling height and root number were significantly decreased with the increase of NaCl concentration,the root length in 0.3%NaCl and 0.6%NaCl treatments was significantly lower than CK treatments;and the fresh weight of seedling in 0.6%NaCl treat-ments was significantly lower than CK and 0.3%NaCl treatments.(2)Chlorophyll accumulation of tropical rice leaves were decreased under salt stress.The contents of chlorophyll a,chlorophyll b and Car in the treatments with 0.3%NaCl and 0.6%NaCl concentrations were significantly lower than CK treatments.The accumulation of proline(Pro),malondialdehyde(MDA)and Na^(+)were increased.The content of Pro and MDA and Na^(+)in the treatments with 0.6%NaCl concentration were significantly higher than treatments with CK and 0.3%NaCl concentration.The accumulation of K^(+)were decreased.The K^(+)content in the 0.3%NaCl and 0.6%NaCl concentration treatments was significantly lower than the CK concentration treatments.(3)Under salt stress,the tiller number,panicle number,panicle length,panicle grain number,thousand-kernel weight and yield of per plant were significantly decreased with the increase of NaCl concentration.