氮素调控对不同穗型超级早稻光合特性和产量的影响

Effects of Nitrogen Regulation on the Photosynthetic Characters and Grain Yield of Different Panicle Types of Early Super Rice

为阐明氮素调控对不同穗型超级早稻光合特性和稻谷产量的影响,以前期试验基础上筛选出的大穗型、多穗型和穗粒兼顾型超级早稻代表品种中早39、陵两优268和淦鑫203为试验材料,采用4种不同施氮量和基、蘖、穗肥比例处理(T1,纯N为0 kg/hm^(2);T2,纯N为112.5 kg/hm^(2),基、蘖肥比例为7∶3;T3,纯N为150.0 kg/hm^(2),基、蘖、穗肥比例为6∶3∶1;T4,纯N为187.5 kg/hm^(2),基、蘖、穗肥比例为5∶4∶1),测定和分析了各处理叶面积、叶绿素含量和光合动态以及稻谷产量。结果表明,T2处理在分蘖期能有效增加所有3类水稻品种的分蘖数,提高冠层叶片叶绿素含量,提高饱和净光合速率。相比T1和T2处理,增施氮素穗肥的T3、T4处理对3类不同穗型品种均能有效提高齐穗后的穗数、冠层上3叶叶面积、叶绿素含量、电子传递速率和实际量子产量,增加稻谷产量,且T3处理3类品种均比T4处理具有更高的收获指数和稻谷产量。多穗型品种陵两优268和穗粒兼顾型品种淦鑫203冠层上3叶叶面积对氮素响应比大穗型品种中早39更明显,但在株高、穗粒数、千粒重等性状上,中早39和淦鑫203对氮素响应比陵两优268更明显。在基蘖肥基础上,适当增加穗肥氮素施用,能有效提高不同穗型超级早稻叶面积、光合速率和有效穗数,最终提高稻谷产量。

To clarify the effects of nitrogen regulation on the photosynthetic characters and gain yield of different panicle types of early super rice,using the large-panicle type,panicle-rich type and panicle-grain type of typical early super rice varieties Zhongzao 39,Linliangyou 268 and Ganxin 203 selected on the basis of the former experiments as the materials,four nitrogen regulation methods of nitrogen rate and ratio of basal,tillering and panicle fertilizers,i.e.,T1,N 0 kg/hm^(2);T2,N 112.5 kg/hm^(2) with the ratio of basal to tillering fertilizers at 7∶3;T3,150.0 kg/hm^(2) with the ratio of basal,tillering and panicle fertilizers at 6∶3∶1;T4,N 187.5 kg/hm^(2) with the ratio of basal,tillering and panicle fertilizers at 5∶4∶1,were designed as the treatments and the leaf area,chlorophyll content,the photosynthetic dynamics and grain yield were measured and analyzed.The results showed that T2 effectively increased the number of tillers,chlorophyll content of canopy leaves and saturated photosynthetic rate of all three types of rice varieties at the tillering stage.Compared with T1 and T2,T3 and T4 with application of panicle nitrogen fertilizer effectively increased the number of panicles,leaf area,chlorophyll content,electron transfer rate and actual quantum yield of upper three leaves of the canopy after full heading stage,and rice grain yield for all three types of rice varieties,and T3 had higher harvest index and grain yield than T4.The varieties of the panicle-rich type Lingliangyou 268 and the panicle-grain type Ganxin 203 had a more significant response to nitrogen than the large-panicle type variety Zhongzao 39 in the leaf area of upper three leaves of the canopy,while Zhongzao 39 and Ganxin 203 had a more significant response to nitrogen than Lingliangyou 268 in the characters of plant height,spikelets per panicle and 1000-grain weight.On the basis of basal and tillering fertilization,application of appropriate amount of panicle nitrogen fertilizer can effectively increase leaf area,photosynthetic rate and productive panicles,and ultimately increase rice grain yield for different panicle types of early super hybrid rice.