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91.
连续两年在慈利县研究了不同耕作方式(翻耕和免耕)和不同油菜秸秆覆盖量(全量、半量、0)对三北2号玉米产量和主要农艺性状的影响,以评价和筛选适合当地的耕作模式。结果表明,与免耕处理相比,翻耕各处理玉米平均产量增加了2.36%~9.11%,且在高温干旱年份(2013年)比雨水较多年份(2014年)增幅大。玉米单产均是秸秆全量覆盖处理半量覆盖处理不覆盖处理。翻耕+秸秆全量覆盖在连续两年的试验中产量均为最高,可在慈利县推广。 相似文献
92.
C. M. Geraldson 《Journal of plant nutrition》2013,36(8):1091-1098
The concentration and balance of nutrients in both the hydroponic or soil solution has been evaluated with relevance to tomato productivity. Yields of 200 mt/ha have been produced in greenhouse, hydroponic culture in a 9 to 10 month period. Yields of more than 100 mt/ha of field grown tomatoes have been produced in Florida in a 4 to 5 month period. Within the limitations of either culture, it is possible per unit of time to provide the nutrients required to produce equivalent yields. It is most significant that field grown tomatoes in Florida can be grown with minimal management and at a fraction of the cost of those grown hydroponically. The validity of the Florida fresh market tomato industry is based on the production efficiency of the field culture. There are annually 16,000 ha of tomatoes grown in Florida, perhaps less than 40 ha grown in hydroponic cultures. 相似文献
93.
《Communications in Soil Science and Plant Analysis》2012,43(13-14):2031-2055
Abstract Aquasorb PR3005A, a hydrophilic polymer (a salt copolymer polyacrylamide), and garden waste compost were added to a loamy sand and a loam soil in pots to assess their impact upon soil physical properties at two different evaporation potentials. Compost was mulched and incorporated, the Aquasorb was incorporated, and their effect on temperature and amelioration of soil water content and evaporation was investigated. Mulching with compost reduced evaporation and increased soil temperature. Maize (Zea mays var. single cross 704) was sown in the same pots later, and growth indicator factors (plant height, fresh and dry weight, root weight, and leaf area) were compared. It was concluded that compost mulch application is beneficial to soil water retention whereas compost incorporation did not show these benefits. Compost mulch advances seedling emergence and enhances early growth through hydrologic soil amelioration. High rates of Aquasorb were also beneficial in advancing the emergence and early growth of maize seeded in loamy sand. The hydration capacity of Aquasorb is reduced as the electrolyte concentration and electrical conductivity are increased. Increased electrolyte concentration in soil solution, through drying, may result in gel dehydration and water release at potentials greater than field capacity, which may be lost to drainage. Furthermore, it is concluded that pot experiments with amendments fail to simulate field conditions. 相似文献
94.
Zhi-Juan Ji Xiao-Guang Wang Yu-Xiang Zeng Liang-Yong Ma Xi-Ming Li Bing-Xin Liu Chang-Deng Yang 《Breeding Science》2012,62(1):71-77
Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind low-yield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (white-pericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice. 相似文献
95.
详细介绍了云南植胶区进行气刺微割采胶新技术试验的研究内容及应用实施情况,通过4 a的微割试验示范研究,比较系统的分析了云南微割采胶试验的产量效应、干含、割胶速度、耗皮量、死皮性状、净增长率等生产性数据。说明了微割采胶新技术具有操作简单、割胶速度快、产量好、节约原生树皮、死皮较轻等特点,并能显著降低割胶劳动强度,有效的提高割胶劳动生产率。全面的掌握了这一新技术的应用原理、实施技术、材料配用、操作规程、安全风险,积累了良好气刺微割推广应用基础。 相似文献
96.
97.
大田土壤耕作层覆膜防渗灌溉栽培水稻研究 总被引:1,自引:0,他引:1
为了推广应用一种新的覆膜栽培水稻方法——覆膜防渗灌溉,对比分析了土壤耕作层覆膜防渗灌溉与常规灌溉条件下水稻的耗水量、水稻生长分蘖状况、水稻产量及土壤中氮磷钾营养元素的变化情况。结果表明,防渗灌溉能明显减少灌溉用水量,较常规灌溉节水9.54%。防渗灌溉可减少土壤中的肥力损失,能有效阻隔土壤中速效钾的淋溶损失。防渗灌溉与常规灌溉的耗水系数分别为711和786 kg/kg,灌耗比分别为0.5和0.6。防渗灌溉降低灌溉水在总耗水量中的比重,减少渗漏损失提高水分利用率。 相似文献
98.
99.
2株优良天麻共生蜜环菌生长条件筛选 总被引:2,自引:0,他引:2
筛选出2株昭通本地天麻共生蜜环菌(SNA03、SNA04)菌索生长的最佳条件。采用单因素试验和正交试验法进行筛选,以生物量为考察指标。2株菌菌索生长的最适温度为25℃,暗培养下菌索生长速度最快;单糖(葡萄糖)为2菌株生长的最佳碳源,有机氮中的酵母膏和蛋白胨为最佳氮源,最适无机元素为K2SO4(SNA03)和KH2PO4(SNA04),最适维生素为VB2;最佳营养条件组合为葡萄糖∶酵母膏∶K2SO4(SNA03)或KH2PO4(SNA04)∶VB2=15g·L-1∶3g·L-1∶2g·L-1∶0.005g·L-)1,氮源(酵母膏)是影响菌索生长的最主要因素。来自昭通的2株天麻共生蜜环菌对营养和环境条件的要求基本一致。最佳生长条件的确定,对昭通蜜环菌快速工业化制种及天麻的大规模生产将起到一定的推动作用。 相似文献
100.