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61.
采用隧道发酵技术,以金针菇(Flammulina filiformis)菌渣为原材料,进行双孢蘑菇培养料的制备。通过一次及二次隧道发酵的工艺控制,检测堆制过程中温度、含水量、pH及电导率等理化成分的变化,并结合出菇结果评价金针菇菌渣培养料的使用情况。结果表明,金针菇菌渣在隧道一次发酵过程中最高温可达74℃以上,整个发酵周期16 d。通过隧道发酵制备的二次培养料不黏腻、结构松散、味道清香,含水量为66.40%,pH为8.16,电导率为875.00μs·cm-1,含氮量2.00%,碳氮比为20.36,符合双孢蘑菇栽培要求。双孢蘑菇四潮出菇产量为19.25 kg·m-2。表明隧道式发酵技术可以应用于工厂化金针菇菌渣制备的双孢蘑菇培养料中。  相似文献   
62.
Traditional seed-coating agents are widespread and used in crop protection. However, the coatings can pose an environmental and health hazard. In this study, a novel wheat seed-coating agent was prepared by using natural polysaccharide as the main raw material, which produces bacteriostatic activity and enhances the germination and quality of seeds. The optimum formula of this seed-coating agent was ultimately determined through a series of laboratory experiments and field trials. The results showed that the yield of wheat seeds treated with this novel seed-coating agent was increased by 10% and its material cost was decreased by 15% compared with the conventional toxic seed-coating agent. The toxicity of the novel seed-coating agent was also less than that of the traditional one. Therefore, this wheat seed-coating agent had obvious economic and environmental benefits.  相似文献   
63.
Olive oil pomace (OLP) contains organic matter and nutrients that could be recycled by composting and supplying it to crops, solving the problem of disposal.

The effects of two OLP composts (C1 and C2) were assessed on two leguminous forage crops commonly cropped in the local livestock farms. In particular, C1 was applied on proteic pea and C2 on clover, compared with a mineral fertilizer (Min) and a commercial organic–mineral fertilizer (Org-min). The influence of composts on some soil chemical properties was also investigated.

The application of C1 significantly increased proteic pea dry weight at the end of the cycle by 27.2% and 52.0% and grain yield by 23.2% and 43.6%, in comparison with Org-min and Min, respectively. The clover dry weight during the entire cycle was lower in C2, in comparison with the other treatments, while no significant difference was found between C2 and the Org-min treatment both in yield and plant height.

Soil nitrate decreased from the beginning to the end of the trial in C1 and C2 plots by 22.8% and 50.9%, respectively. Soil phosphorous content significantly increased in Min by 32.4 and 41.7% compared to C1 and C2, respectively. These results showed that the substitution of commercial fertilizers with compost could be an environmentally sustainable solution. The high presence of heavy metals in compost should not affect soil application at least in this short-term trial.  相似文献   
64.
国家农业部部长何康同志是我国天然橡胶业的创业者和领导者之一,文章通过有关重大史实的记述,展现出何何康同志一直在关心和指导云南天然橡胶业的创造和发展的至深情怀。  相似文献   
65.
天然林保护工程封山育林国家投资标准探讨   总被引:1,自引:0,他引:1  
以重庆市涪陵区2012年天保工程封山育林规划设计概算为依据,将涪陵区现行天保工程封山育林按国家标准的投资进行细分,在此基础上结合实际情况进行重新调整,提出了天保工程封山育林新标准,为确定天保工程封山育林标准提供参考。  相似文献   
66.
梯室淡毛三节叶蜂Arge reversinervis Wei是危害刺榆Hemiptelea davidii的新害虫。对梯室淡毛三节叶蜂的卵、幼虫和蛹的形态特征进行描述,并首次对其生物学特性进行了研究。梯室淡毛三节叶蜂在海城1 a发生1代,以预蛹在土壤中越冬,翌年4月上旬化蛹,4月下旬成虫开始羽化,5月中旬卵开始孵化,6月上旬幼虫下树做茧越夏越冬。梯室淡毛三节叶蜂的天敌主要有显背臀姬蜂Notopygus insignis Kriechbaumer、褪色前眼茧蜂Proterops decoloratus Shestakov、叶蜂啮小蜂Tet-rastichus sp.及白僵菌Beauveria bassiana(Bals.)。  相似文献   
67.
Abstract

Laboratory and greenhouse studies were conducted on six soils from natural reserves, seven plantation soils, and two arable soils from the Omo biosphere reserves in southwestern Nigeria to assess the phosphorus (P) fractions and the extent to which the soils could support five consecutive cycles of maize (Zea mays L.) harvest. The organic‐P fractions constitutes about 50% of the total P, and the inorganic‐P fractions in the order of abundance was iron (Fe) P>occluded P>aluminum (Al)‐P>calcium (Ca) P. The residual P constituted about 20% of the total P. There were significant reductions in the inorganic‐P fractions after five consecutive maize harvests; this was however, more pronounced in the available P (Bray 1). About 62% reduction in Bray 1 P was recorded after maize harvests. The reductions in the P forms after five cycles of maize harvest was Bray 1 P>Ca P>residual P>Al P>total P>Fe P>organic P>occluded P>reductant P. The capacity of the soils to support maize growth without fertilization varied widely in each of the maize cycle. Soil from natural reserves produced a significantly higher maize yield compared to most plantation soils. The arable soils investigated were depleted of their fertility after the third crop harvest.  相似文献   
68.
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   
69.
蓝靛果忍冬色素提取工艺的研究   总被引:2,自引:0,他引:2  
以蓝靛果忍冬果实为原料,进行了天然色素提取工艺研究。结果表明:蓝靛果忍冬色素最佳的提取工艺条件为:提取剂采用无水乙醇效果较好,用量为35mL;提取pH 3、最适合的提取温度为80℃、60min为最佳的提取时间。  相似文献   
70.
古尔班通古特沙漠南缘蜱携带无形体的调查   总被引:1,自引:0,他引:1  
为了解古尔班通古特沙漠南缘蜱携带无形体的状况,在该地域3个不同生境区域11个地点采集家畜寄生蜱标本,进行分类鉴定;运用套式PCR筛选无形体阳性蜱样本,并用半套式PCR扩增无形体科16SrRNA基因5′端高变区,进行克隆测序;将所获得的DNA序列与GenBank收录的序列作比对,并用Mega 5.0软件构建系统发育树,鉴定蜱携带无形体的种类。结果共采集708只蜱,鉴定为4个属8个种。在分类后的236份蜱样本中,检测出无形体阳性25份,阳性率为10.59%。序列比较发现,在亚洲璃眼蜱、血红扇头蜱、残缘璃眼蜱、长角血蜱中分别存在查菲埃立克体(Ehrlichia chaffeensis)、犬埃立克体(Ehrlichia canis)、边缘无形体(Anaplasma marginale)和绵羊无形体(Anaplasma ovis)的16SrRNA基因片段。研究结果证实在古尔班通古特沙漠南缘家畜寄生蜱中携带无形体,提示该地域可能是无形体病的自然疫源地。  相似文献   
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