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21.
通过对保护地、露地向日葵菌核病的调查,总结出大通县向日葵菌核病的病原和感病症状。结合调查研究提出综合防治措施。 相似文献
22.
本试验用室内幼苗接种的方法,对内蒙古地区栽培的的7个向日葵品种进行抗锈病性的鉴定,结果表明:益民大白花葵、迪卡.杂交油葵、S40(Hyole ic40)油葵、S31(HySun33)油葵呈抗锈病反应型;益民星火花葵、益民大青花葵、益民花葵二号呈感锈病反应型。其中益民花葵二号最感病,S31(HySun33)油葵最抗病。 相似文献
23.
24.
Sustainable food production in semi-arid tropical countries can be achieved through efficient utilization of rainwater. A field experiment to assess the grain yield, seasonal water use (WU), water use efficiency (WUE) and precipitation use efficiency (PUE) of sunflower (Helianthus annuus L.) intercropped with cowpea (Vigna unguiculata L.) on two tillage systems was conducted during the 2007/2008 and 2008/2009 cropping seasons at the University of Venda (22°58′ S, 30°26′ E at 596 m above sea level). The experiment was configured as a 2 × 2 × 2 factorial design with three replications. The tillage treatments were conventional tillage (CT) (control) and in-field rainwater harvesting (IRWH) system. The IRWH is a special crop production technique that promotes runoff on 2.0-m wide no-till strip between crop rows and collects the runoff water in basins where it infiltrates into the soil profile. The treatments in the cropping system (CS) consisted of a sole crop (sunflower or cowpea) and an intercrop (sunflower × cowpea). Results of the experiment revealed that IRWH led to a significant (P < 0.05) increase in sunflower grain yield in the second season but cowpea grain yield was not influenced by tillage systems. IRWH resulted in significantly higher WU, WUE and PUE of both crops compared to CT system in the second season. The CS had significant effects on sunflower grain yield in both seasons but none on the cowpea grain yield. WU was significantly higher in intercrops than in sole cowpea and sole sunflower in the first and second season, respectively. WUE and PUE were significantly greater in sole sunflower than in the intercrops but less in the sole cowpea than in the intercrops. 相似文献
25.
1990—1992年三年试验结果表明,尽管只施氮磷肥可获得高产,但在施氮磷肥的基础上按比例配施钾肥,可进一步提高向日葵的产量.钾肥的最佳经济施肥量为150公斤K2O/公顷,N、P2O6、K2O最适比例为2∶1∶2. 相似文献
26.
本试验通过对接种黄萎病的地块进行不同浇水次数的处理来调查分析浇水次数对向日葵黄萎病发生程度及产量的影响.结果表明随着浇水次数的增多,向日葵黄萎病的发病严重度也随之增加,且向日葵的产量呈现降低的趋势.在接种的地块中浇水1次的病情病指由29.0递增到浇水3次51.5;产量则由浇水1次的4690.95kg/公顷降低至浇水3次的3815.55kg/公顷. 相似文献
27.
无鱼粉日粮在蛋鸡生产上的应用研究 总被引:1,自引:0,他引:1
利用酵母和葵花粕代替日粮中的鱼粉组成无鱼粉日粮,以无鱼粉日粮和有鱼粉日粮对蛋鸡进行试验,结果为:饲喂无鱼粉日粮的试验组和饲喂鱼粉日粮对照组的产蛋率分别为67.96%和65.01%,不存在差异(P>0.05);只平均产蛋量为44.73和42.41g,存在差异(P<0.05);平均蛋重为65.83和62.29g,不存在差异(P>0.05);死亡率分别为1.69%和2.1%,不存在差异(P>0.05);试验组比对照组每生产1kg蛋饲养成本降低1.9%。因此无鱼粉日粮可代替鱼粉日粮在蛋鸡生产上应用。 相似文献
28.
为了进一步了解向日葵与向日葵锈病病菌的互作关系及品种的抗性机制,采用电子显微镜技术对向日葵品种对锈病抗性的组织学和超微结构进行研究.在电镜下观察发现,向日葵锈病菌侵染向日葵后,在感病品种和抗病品种上发育的组织学和超微结构特征有明显差异.病菌在感病品种细胞间隙分布有大量的胞间菌丝,寄主细胞发生质壁分离;叶绿体变形,叶绿体的片层结构排列零乱,直至叶绿体解体.在抗病品种上表现为菌丝生长受抑,没有观察到吸器的产生,寄主细胞的早期坏死与锈菌的发育受阻密切相关.品种的抗病性可能与饥饿阻止真菌生长有关. 相似文献
29.
Supplementation of dairy cows with a fish oil containing supplement and sunflower oil to increase the CLA content of milk produced at pasture 总被引:1,自引:0,他引:1
It has been shown that the cis 9, trans 11 isomer of conjugated linoleic acid (CLA) can be increased in milk by supplementation with fish oil and vegetable oils. Feeding a high level of oil, however, can impact negatively on gross milk composition. The principal aim of this study was to determine if relatively low levels of fish oil or sunflower oil, either alone or in combination, offered to dairy cows on pasture would increase the C18:2 cis 9, trans 11 CLA concentration in milk. Forty autumn-calved cows on a diet of grazed grass were assigned to 4 supplementation treatments: (i) No supplement (P), (ii) 255 g/day of sunflower oil (SO), (iii) 255 g/day of sunflower oil + 52.5 g/day of fish oil (SOFO), and (iv) 105 g/day of fish oil (FO). The fish oil was supplied in a proprietary product called Omega-3 Supplement which is a mixture of marine oils and an extracted oilseed meal and contains 500 g/kg of oil. The oils were fed in a concentrate mixture, which was offered at a rate of 3.0 kg/cow per day. The production of the cows was measured for 54 days and the milk fatty acid composition was determined on day 0 (immediately before the supplements were introduced) and on days 14, 28 and 42 after the treatments were imposed. Supplementation increased the yield of milk (P < 0.01), protein (P < 0.05) and lactose (P < 0.001), decreased milk fat (P < 0.05) and protein (P < 0.01) concentrations and increased (P < 0.01) lactose concentration. Type of oil did not significantly affect any production variable. The concentration of C18:1 trans 9 + C18:1 trans 11 (mainly C18:1 trans 11) (P < 0.001) and C18:2 cis 9, trans 11 CLA (P < 0.01) were greater on supplemented treatments than on P and the concentration of both were greater (P < 0.05) on FO than on SO. The results confirm that the concentration of C18:2 cis 9, trans 11 CLA can be increased further, from an already relatively high concentration in milk from pasture, by offering supplements containing a low level of fish oil either alone or in combination with sunflower oil. 相似文献
30.
黄土高原向日葵产量的土壤养分限制因子与施肥指标研究 总被引:3,自引:0,他引:3
1994~1996年在黄土高原陕西渭北旱塬进行了向日葵的养分限制因子与高产高效施肥试验,结果表明,N、P、K是向日葵产量的限制因子。Fe、Zn、Mg、Cu、Mn、B为非限制因子,限制因子对向日葵的产量效应K>N>P,经济效应最佳施肥指标N163.21~169.89kg/hm2,P2O5128.60~131.91kg/hm2,K2O181.37~190.09kg/hm2。 相似文献