Influence of neem on susceptibility of Beauveria bassiana and investigation of their combined efficacy against sweetpotato whitefly, Bemisia tabaci on eggplant     

Md. Touhidul Islam 《Pesticide biochemistry and physiology》2010,98(1):45-3413

A study on the compatibility of the entomopathogenic fungus Beauveria bassiana with neem was conducted against sweetpotato whitefly, Bemisia tabaci, on eggplant. Initially, three concentrations of neem (0.25%, 0.5% and 1.0%) were used to investigate the physiological responses of B. bassiana. Thereafter, above three concentrations of neem along with three concentrations of B. bassiana (10⁶, 10⁷ and 10⁸ conidia/ml) were used to investigate combined deterrence index, DI under two application methods (foliar and soil) of B. tabaci. Significant differences were observed among neem concentrations on all variables- germination percentage, vegetative growth, number of conidia, amount of biomass and proteolytic activity of B. bassiana. The reduction percentage of germination, vegetative growth, sporulation, biomass production and proteolytic activity of B. bassiana were as high as 12%, 13%, 35%, 38%, and 34%, respectively, to neem. Significant differences were also observed on deterrence index, DI (adult and oviposition) of B. tabaci. The current study investigated that the highest adult DI (80.15) and oviposition DI (88.25) occurred when 1.0% neem was combined with 10⁸ conidia/ml of B. bassiana. As the results show, neem is compatible with B. bassiana; and soil application of neem along with foliar application of B. bassiana might be useful for the control of B. tabaci.  相似文献   

中国土壤侵蚀定量研究进展   总被引：10，自引：0，他引：10  

李勉  李占斌  刘普灵 《水土保持研究》2002,9(3):243-248

小流域是水土流失综合治理的基本单元,定量研究其侵蚀产沙的空间分布,对于水土保持措施的实施有着重要的意义。作为土壤侵蚀重要的研究热点之一,土壤侵蚀定量研究在我国已有50年之久,回顾并总结过去的研究成果对于今后更好地开展研究工作十分必要。在简要回顾了我国土壤侵蚀定量研究的过去与现状的基础上,主要就降雨特性、坡度、坡长、坡向、植被盖度及土地利用方式等影响因子与土壤侵蚀的定量关系研究,以及小流域侵蚀产沙定量研究方面的最新进展进行了归纳和总结,并针对各方面存在的问题以及有待深入研究的问题进行了探讨。  相似文献   

提高甘蓝型油菜下胚轴愈伤组织诱导率的研究   总被引：1，自引：0，他引：1  

杜坤  范芸  吴冕  周晓燕  高亚楠  王幼平 《扬州大学学报(农业与生命科学版)》2012,33(2):58-61

采用油菜幼苗下胚轴作为外植体,分析不同品种、苗龄以及激素配比对愈伤组织出愈率的影响。结果表明:相同条件下,扬油6号的出愈率最高;扬油6号在5d苗龄、预培养3d以及加入0.1mg·L-1 2,4-D、1.0mg·L-1 6-BA、5.0mg·L-1 AgNO3条件下的愈伤组织诱导率最高。  相似文献   

Isolation and Molecular Characterization of Fowl Adenovirus and Avian Reovirus from Breeder Chickens in Japan in 2019–2021     

Makiko YAMAGUCHI  Yu MIYAOKA  Md. Amirul HASAN  Md. Humayun KABIR  Dany SHOHAM  Harumi MURAKAMI  Kazuaki TAKEHARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):238

Fowl adenoviruses (FAdVs) and avian reoviruses (ARVs) are ubiquitous in poultry farms and most of them are not pathogenic, yet often cause damage to chicks. A total of 104 chicken fecal samples were collected from 7 farms of breeder chickens (layers and broilers) in Japan from 2019 to 2021, and yielded 26 FAdV plus 14 ARV isolates. By sequencing, FAdV isolates were classified as FAdV-1, 5 and 8b. ARV isolates were classified as genotype II, IV and V. These results suggest that FAdVs and ARVs are resident in the breeder chicken farms in Japan.  相似文献   

Dietary carbohydrate modifies the density of L cells in the chicken ileum     

Md SALAHUDDIN  Kohzy HIRAMATSU  Iori NISHIMOTO  Kazumi KITA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):265

Glucagon-like peptides (GLPs) are secreted from intestinal L cells and stimulate various physiological functions in the gastrointestinal tract. The secretion of GLPs is influenced by macronutrient ingestion. This study aims to clarify the effects of dietary carbohydrate (CHO) on L cells in the chicken ileum. Six-week-old, male White Leghorn chickens were divided into three groups: control, low-CHO and CHO-free, with five chickens in each group. Paraffin sections were made from the proximal and distal ileum of each animal and subjected to immunohistochemistry for GLP-1 and GLP-2 peptides and in situ hybridization for proglucagon (PG) mRNA. A significant reduction of GLP-1- and GLP-2-immunoreactive cells was observed in the two experimental groups compared with that in the control. A reduction of cells expressing PG mRNA was observed in the proximal and distal ileum of the CHO-free group compared with that in the control. The ratio of GLP-1-immunoreactive cells showing Ki-67 immunoreactivity was significantly lower in the distal ileum of the CHO-free group than that in the control group. These data suggest that dietary CHO is an effective stimulator for modifying L cell density in the chicken ileum.  相似文献   

湖北烟田地块特征与田间作业农机适用性分析     

吴元华  申国明  王勉  徐晓波  陶德欣  姜芳  刘阳  尹刚华 《农学学报》2023,13(1):51-60

为进一步明确山区丘陵烟区田间生产农机适用性的限制因素。以湖北鹤峰农机生产核心示范区为研究对象,对该区域使用率较高农机分型,对生产环节分类,确定农机合理的田间作业路径;对与农机作业相关地块特征值进行测算。通过农机作业参数与田块作业条件匹配度分析,结果显示,影响区域农机机型选配的首要因素是机耕路条件,其次是地块形状和面积,其中,地块形状对轮廓平行移动方式作业农机机型影响较大,地块宽度决定选择农机机型大小。当前地块生产条件下,3～5 kW和11～18 kW小微型农机适用性较高,37～66 kW农机适用于2001 m²以上较规则且有机耕路条件的田块。  相似文献   

Phytotoxic potential of Chrysopogon aciculatus (Retz.) Trin. (Poaceae)     

Md. Shafiqul Islam  Farhana Zaman  Arihiro Iwasaki  Kiyotake Suenaga  Hisashi Kato‐Noguchi 《Weed Biology and Management》2019,19(2):51-58

The creeping weed, Chrysopogon aciculatus (Retz.) Trin., is widely known for its use as folk medicine, while its phytotoxic potential has not been examined. Therefore, we carried out an investigation into the phytotoxic potential of C. aciculatus to identify phytotoxic substances. C. aciculatus extracts showed inhibitory effects on shoot and root growth of cress, lettuce, rapeseed, and Italian ryegrass. Inhibition was both species‐dependent and concentration‐dependent. Two substances, (9S,10E,12Z)‐9‐hydroxyoctadeca‐10,12‐dienoic acid (9‐HO‐ODDEA) and rhizopycnin A, were isolated using chromatographies and characterized by spectral analysis. 9‐HO‐ODDEA retarded shoot and root growth of cress at concentrations higher than 1.0 and 0.3 mM, respectively, while on cress seedling by rhizopycnin A, the inhibition began from 1.0 mM. The concentrations needed for 50% inhibition of the shoot and root growth of test plants ranged from 1.71–2.31, and 0.71–0.72 mM for 9‐HO‐ODDEA and rhizopycnin A, respectively. These results indicate that these substances may contribute, to a certain extent, to the phytotoxic activity of C. aciculatus.  相似文献   

Pyramiding three rust‐resistance genes confers a high level of resistance in soybean (Glycine max)     

Naoki Yamanaka  Md. M. Hossain 《Plant Breeding》2019,138(6):686-695

Pyramiding Asian soybean rust (ASR) resistance (Rpp) genes in a single genotype has been shown to increase ASR resistance in soybean. However, it remains unclear which combinations of Rpp genes are superior. Therefore, here, we developed six new Rpp‐pyramided lines carrying different combinations of Rpp genes and evaluated their resistance against 13 Bangladeshi rust (Phakopsora pachyrhizi) isolates (BdRPs) alongside seven previously developed Rpp‐pyramided lines. We found that lines carrying one, two and three Rpp genes had high ASR resistance without sporulation in 13.8%, 35.2% and 73.1% of the assays, respectively. Among the new lines that were developed, those with Rpp3 + Rpp4 and Rpp3 + Rpp4 + Rpp5 had high levels of ASR resistance, while the line containing Rpp2 + Rpp4 + Rpp5 showed immunity phenotype at two weeks after inoculation by the BdRP‐22 infection. Thus, pyramiding larger numbers of Rpp genes confers soybean with a higher level of resistance to ASR pathogens and can produce an immunity phenotype at two weeks after inoculation.  相似文献   

Comparison of rice straw and bamboo stick substrates in periphyton-based carp polyculture systems     

Sunila Rai  Yang Yi  Md Abdul Wahab  Amrit N Bart  & James S Diana 《Aquaculture Research》2008,39(5):464-473

An experiment was conducted to compare rice straw mat and kanchi (bamboo sticks) as substrates in periphyton‐based polyculture systems. The experiment had three treatments: (a) no substrate (control), (b) rice straw as a substrate (3 × 2.7 kg pond^?1) and (c) kanchi as a substrate (390 kanchi pond^?1). Fingerlings (n=40) of rohu, Labeo rohita (24.5±0.5 g); mrigal, Cirrhinus mrigala (25.1±0.6 g); catla, Catla catla (25.8±0.5 g); common carp, Cyprinus carpio (27.6±0.6 g), and silver carp, Hypophthalmichthys molitrix (30.4±0.9 g) were stocked at a 3:2:2:2:1 ratio and cultured for 90 days. There were no differences in the number of plankton, periphyton and macro‐zoobenthos among the treatments. The total plate count of bacteria was higher in the rice straw treatment (41 320 million cfu m^?2) than that in the kanchi treatment (11 780 million cfu m^?2). Growth and the final mean weight of rohu, catla and common carp were higher in the substrate treatments than those in the control. Rice straw and kanchi treatment, respectively, resulted in 38% and 47% higher combined total weight gain over control. Gross margin analysis showed that rice straw treatment resulted in more profit than the control and kanchi treatment. Therefore, rice straw has the potential to be used to increase production in the low‐input rural aquaculture.  相似文献   

Effects of tilapia (Oreochromis niloticus L.) stocking and artificial feeding on water quality and production in rohu–common carp bi‐culture ponds     

Mohammad Mustafizur Rahman  Marc Verdegem  Md Abdul Wahab 《Aquaculture Research》2008,39(15):1579-1587

Previous research showed that stocking 1.5 rohu (Labeo rohita) and 0.5 common carp (Cyprinus carpio) m⁻² yields the highest production in small holder ponds in Bangladesh. The present study looked into the effects of additional stocking of Nile tilapia (Oreochromis nilotica) in fed or non‐fed ponds on water quality and fish production. A low, additional stocking density of 0.2 Nile tilapia m⁻² was tested. All treatments were executed in triplicate in 100 m² ponds and the duration of the experiment was 4.5 months. The results showed that tilapia addition increased nutrient concentrations and reduced total suspended solid concentration and phytoplankton biomass (P<0.05). Tilapia stocking resulted in additional production without affecting the growth and production of rohu and common carp. Supplemental feeding increased the nitrogen and phosphorus concentrations, phytoplankton availability and the growth and production of rohu and common carp (P<0.01). The combination of supplemental feeding and tilapia stocking resulted in a higher net yield than the other treatments (P<0.05). Stocking 1.5 rohu, 0.5 common carp and 0.2 tilapia m⁻² in fed‐ponds is a good culture combination for polyculture farmers in South Asia.  相似文献