硫肥对双低油菜产量与品质的影响

EFFECT OF SULFUR APPLICATION ON YIELD AND QUALITY OF CANOLA DOUBLE LOW OILSEED RAPE (BRASSICA NAPUS CV. OSCAR)

在澳大利亚新南威尔士州缺硫土壤上进行了硫、氮不同水平组合对双低油菜(Canola)的影响试验。结果表明,试验条件下施用硫肥可显著提高油菜产量及含油量。低硫(S_(10))或无硫(So)条件下,一定量的氮肥(N_(80))可提高子粒内的含硫量,但高硫条件下,高量氮肥则降低含硫量。植株体内的含硫量随生育进程趋于降低。施硫处理在抽苔期出现一吸硫高峰,而对照呈指数下降;但在开花期与角果充实期则保持相对稳定。氮肥对生长前期(莲座期与抽苔期)植株(茎、叶)含硫量的影响不显著,而中、后期(开花、角果充实期),则随施氮量的增加而显著降低。高量氮肥(N_(160))会降低子粒内的硫代葡萄糖甙含量;施硫,特别是在高施硫量条件下,其含量则明显增加,但仍远低于子粒硫代葡萄糖甙40μmol/g的标准,因而不会影响脱油饼粕的饲喂质量。

Sulfur (S) and nitrogen (N) applicaton to canola (double low oilseed rape) was conducted on S deficient soil in New South Wales, Australia. The results indicated that sulfur supply increased seed yield and oil content significantly, certain amount of N (eg. N80) with low (S10) or without S (S0) might increase seed S concentration but high rate N with high S could depress it. Generally, S concentration in vegetative parts were decreased with plant development. There was a peak of S uptake appearing at stem elongation with S supply (Y-0. 0156X2+0. 0012X+0.5276, R2=0. 804) but exponential decrease (Y-3. 7205X-0.595, (R2-0.935) without S. The S concentration in vegetative parts remained relatively stable during flowering and pod filling stages. There was no significant effect of N supply on vegetative S concentration during earlier growth stages (eg. rosette and stem elongation) but the concentration at middle and late stages (eg. flowering and pod filling) was significantly decreased by N application. Total glucosinolates were decreased by high rate N (N160) but increased by S because of a close correlation between seed S and glucosinolate concentration (Y=1.1572e3.5289x, R2 -0. 8273). However, even at highest rate of S, the glucosinolate concentration was still far below the standard (40u mol/g in whole seed) so that the oil free meal would not affect feeding quality of animals.