Effects of Split Application of Fertilizer and Planting Density on Yield, Components of Yield and Other Agronomic Characters of Rice (Ⅱ)

水稻肥料分施與栽植密度對產量，產量構成因子及其他主要農藝性狀之效果（二）

張萬來(W. L. Chang) ； 楊遜謙(S. C. Yang)

《中華農業研究》 13卷4期 (1964/12) Pp. 1-10

https://doi.org/10.29951/JARC.196412.0001

摘要

本試驗仍分肥料施用法與栽植密度兩因子。肥料施用法（第一因子）分4個變級，郎慣行施肥法（基肥，N1/2, P, K全量，全層施肥；第一次追肥，N1/2於插秧後30日施用），分施法1（基肥，N1/5, P, K2/3，全層施肥；第一次追肥，N5/2於插秧後30日施用；第二次追肥N2/5, P, K1/3於插秧後60日施用），分施法2（基肥N4/10, P, K2/3，全層施肥；第一次追肥N3/10，於插秧後30日施用；第二次追肥N3/10, P, K1/3於插秧後60日施用），與分施法3（基肥N3/10, P2/3, K3/5，全層施肥；第一次追肥N3/10於插秧後30日施用；第二次追肥N3/10, P1/3, K2/5於插秧後60日施用；第三次追肥，N1/10於插秧後80日施用）。栽植密度（第二因子）分兩個變級，郎慣行栽植密度（每坪64株）與密植（每坪96株）。兩個因子計得8種試項，隨機區集設計重覆4次。本試驗於民國53年第一期作，在嘉義農業試驗分所舉行，以明瞭各因子對第一期作水稻產量及主要農藝性狀之效果。茲將所得結果摘要如下：
肥料分施，除分施法1外，均較慣行施肥增產，其增產原因爲每株穗數與每穗粒數增加所致。分施法3產量最高，每公頃乾淨谷較慣行法層加579公斤，達10.75%，差異顯著。氮肥分施以4次最佳，惟每次追肥量所佔比例似不宜過高。鉀肥分施兩次有效但磷肥分施效果不明。密植對慣行栽植密度每公頃乾淨谷可增加463公斤，達8.41%差異極顯著。其產量之提高乃得自單位面積內總穗數之增加。
水稻初期發育顯受肥料分施抑制，分蘗與株高，肥料分施區者均顯著低減。惟在發育後期，穗數，株高，穗長與穗重均以肥料分施區者爲優。肥料分施顯著減低谷粒千粒重。生育日數與叶稻熱病之發生受肥料分施影響較少，但穗頸稻熱病之發生，則因肥料分施而顯著增加。分蘗與穗數隨栽植密度之增加而顯著低減，其餘農藝性狀亦有類似趨勢，惟差異均不顯著。
稻莖第一節間以下各節問長度均因肥料分施而顯見增加，尤以第三節問及第五節問爲最。第三節間與第五節間長度與倒伏似有密切關係，因該節間愈長，其倒伏百分比亦愈高。密植亦有增加倒伏之趨勢，惟差異未達顯著水準。
肥料分施與栽植密度之間似無顯著之交感作用存在。

並列摘要

The rice variety, Chianung 242 was subjected to 4 levels of fertilization and two levels of planting density arranged in a 4×2 factorial oxperiment with four replications. The experiment was conducted at Chiayi Agricultural Experiment Station in the first crop of 1964. Data on grain yield, components of yield and several other agronomic characters were taken to analyze the effects of the treatments as well as their interactions.
Split fertilizaions generally produced higher yields than conventional one, a difference exceeded the 5% level of probability. The yield increase appeared to be due largely to the increase of panicles and grains.
Responses of grain yield as well as other agronomic characters measured to the split application of phosphoric fertilizer were not evident. However, there were indications for the effects of split applications of nitrogen and potash fertilizers.
Splitting nitrogen four times with the ratio of 3: 3: 3: 1 during the entire period of growth gave, so far, the highest grain yield. Higher dosages of nitrogen applied at the first top-and second top-dressings resulted in the decrease of grain yield, severe occurrence of neck blast disease and lodging, suggesting that splitting ratio of 6: 3: 3 was better than that of 2: 4: 4 under the conditions of this experiment. For potash fertilizer, the splitting ratio of 6:4 gave better grain yield than that of 6.7: 3.3. Applying first top-, second top-, and third top-dressings at stages of maximum tillering, floral primordia differentiation and spiklet and pollen mother cell differentiations, respectively, appeared to be effective. However, other alternatives should also be explored.
The high planting density produced higher yield than lower one, a difference exceeded 1% level of probability. The yield increase was attributable to the increase of panicles per unit area.
Rice plants in the plots of split fertilizations generally tillered less with shorter culms in the early stage of growth, but they overgrew those of conventional fertilization for these characters at the maturing stage. The panicles of split fertilizations were generally heavier and longer than those of coventional one. Number of tillers, plant height, panicle weight and panicle length were generally decreased in the plots of high planting density.
Split fertilzations significantly stimulated the occurrence of neck blast disease which, in turn, caused a reduction in grain weight. Planting density did not affect the occurrence of rice blast disease.
Split fertilizations significantly increased the length of internodes especially that of the third and the fifth internodes. The elongation of internodes, especially at the third and the fifth, seemed to be related to the severe lodging of the plots treated with split fertilizations. The results suggested that the practice of split fertilization in the first crop should take into account the occurrence of blast disease and lodging. Planting density did not cause a significant change in the length of internodes. However, there was tendency for a high planting density to accompany a higher percentage of lodging.
There were no significant interactions between the split application of fertilizers and planting density for all the characters measured in this experiment.