Effects of Leaf Area Index, Specific Leaf Area, Nitrogen Content in Leaves and Distribution Ratio of Dry Matter to Pod on Net Assimilation Rate of Peanut Plants in the First Half of Fruiting Stage

Abstract

The author examined effects of leaf area index(LAI), specific leaf area(SLA), nitrogen content in leaves (NL), and distribution ratio of dry matter to pod(PD.R) on net assimilation rate(NAR) in the first half of fruiting stage of peanut plants cultivated under six management factors. The results obtained were as follows.: 1. NAR was affected significantly by mulching, planting date, planting density and number of plants per hill (Table 3). 2. The correlations of NAR with LAI, SLA and PD.R were significantly negative, respectively. But, the correlation between NAR and NL was significantly positive (Fig. 1, Table 4). 3. LAI, PD.R and SLA were selected as independent variables in the best regression equation for determining NAR that accounted for 85 percent of the variation of NAR(Table 5). 4. By comparison of the standard regression coefficients in the equation, it was recognized that the relation of the variables to NAR become stronger in the order of SLA, PD.R and LAI (Table 6). 5. In carrying out growth analysis of peanut plants in the fruiting stage, it is necessary to remark PD.R as an important factor affecting NAR.