摘要
在溶液培养条件下研究了不同介质pH和氮形态对5种不同的水稻(Oryza sativaL.)基因型(常规籼稻、杂交籼稻、常规粳稻、杂交粳稻和旱稻)根部通气组织形成的影响。结果表明,不同形态的氮与不同介质pH对水稻根通气组织形成的影响存在基因型差异。以NH4+-N为单一氮源时,低pH(pH 4.5)更有利于籼稻根的通气组织形成,而粳稻和旱稻根通气组织的形成受介质pH的影响不明显。以NO3--N为单一氮源时,近中性条件(pH 6.5)更有利于粳稻和旱稻根的通气组织形成,介质pH对籼稻根通气组织形成的影响未显示出明显差异。低pH条件下且以NH4+-N为单一N源时,稻根皮层处更易形成通气组织,可能是植物为了减轻低pH条件下铵毒害而产生的一种适应性机制。
Solution culture experiments were carried out to study the effects of different medium pH （pH 4.5, pH 6.5） and N forms （NH4^＋-N, NO3^--N） on arenchyma formation in roots of five rice genotypes. The five genotypes were as follows： conventional indica （Yangdao No.6）, hybrid indica （Shanyou 63）, conventional japonica （Nongken 57）, hybrid japonica （Siyou 917） and upland rice （Baxi upland rice）. Results showed that the effects of N forms （NH4^＋-N, NO3^--N） and medium pH （pH 4.5, pH 6.5） on arenchyma formation in roots varied with rice genotypes. Low pH （4.5） had negligible effects on aerenchyma formation in roots of japonica （conventional japonica, hybrid japonica） when the NH4^＋-N was the sole N source; while low pH level （pH 4.5） stimulated indica rice （conventional indica, hybrid indica） to form aerenchyma in roots in case providing the same N source. Under the condition of NO3^--N being the sole N source, near neutral pH （pH 6.5） was more favorable to form aerenchyma in the root of japonica rice and upland rice, while the effect of medium pH on the aerenchyma formation of indica rice did not show a statistical significance. Under the low pH condition with NH4^＋-N as the sole N source, aerenchyma could be formed much easier in the root cortex of rice. This might be an adaptable mechanism of plant to decrease toxicity of ammonium accumulation under low pH condition.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2006年第2期195-200,共6页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金项目(30270783)资助
