2 Effects of cultivation measures on grain protein, lysine and starch content Protein content, protein accumulation amount and protein accumulation rate ingrains increased with the increase of nitrogen application amount and top dressing N ratio or with the proper decrease of plant density.
Increasing fertilizer N and close planting can increase the number of the ears per unit area,so,It is the most important way to give enough fertilizer N(200～210 kg per ha) and then proper close planting(30.0 cm×13.4～14.4 cm)
New 90-3"is a very premature new breed of paddy. According to the trail of plant in jar,the best seedtime is between 10 May and 20 May. Under the circumstances of planting proper postponement,the seeding number per hole are not less than 7, the average of leaf laminas are 14,the elongate internodes are 5,and the leaves in the critical leaf age of valid tiller are 9.
Conclusion: The proper fertilizer proportion of P. tenuifolia is N:P:K=1:1.04:1.34, and the amount of fertilizer applied is annually urea 26kg, concentrated superphosphate 27kg and potassium sulphate 32kg for per 667m2.
The results obtained are as follows: (1) The genotypes with high absorption ability of potassium is not probably high in use efficiency. It is essential for the plant to get a proper potassium accumulation.
And new method of estimating those genetic effects have been developed by designing a series of crosses. This method is helpful to the proper estimation of the practical values of the male sterile lines of various rice male-sterile cytoplasm resoures and to the further study about how the male sterile cytopasms affect the main characters in hybrid F_1.