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1.
Ethylene was tested as a sprout inhibitor on potatoes intended for processing over the 2006-2007 and the 2007-2008 storage seasons. Russet Burbank, Shepody, Innovator, FL-1867, and FL-1833 were loaded into the University of Maine potato research facility in October of 2006. Ethylene gas was metered into the storage until a concentration of 0.1 ppm was reached and then held for one week. At weekly intervals, the ethylene concentration was increased to 0.3 ppm, 0.6 ppm, 12 ppm, 5.0 ppm and 102 ppm. Subsequently, the concentration was maintained at 10.0 ppm for the duration of the storage season. Control potatoes received chlorpropham (CIPC) for sprout control. The trial was repeated in the 2007-2008 storage season. The Agtron readings were performed on the processed potatoes at the end of the storage season. There was no difference in the US color grade between the CIPC-treated and ethylene-treated tubers within any tested variety in either storage season. Sprout inhibition of the ethylene-treated potatoes was acceptable for normal storage length of the potato varieties tested. Ethylene may have promise as an alternate to CIPC for sprout control in potato storages.  相似文献   

2.
Pot experiments were conducted in a glasshouse to determine the growth pattern of lettuce, true potato seedlings (TPS) and single node cuttings of TPS in response to biochar. The treatments were arranged in a randomized complete block design with 5 treatments (0, 10, 30, 50 and 100 t ha^-1) ofbiochar from greenwaste with 5 replications in lettuce, 10 in TPS and 5 in single node cuttings of TPS. The observations recorded on growth parameters showed that biochar had significant effect on growth of lettuce but no consistent effect on growth of TPS and single node cuttings. Among the biochar rates, 30 t ha^-1 had the greatest influence on overall growth of lettuce. The pH and electrical conductivity increased as the biochar rates increased in all experiments. These results provide an avenue for soil management system by using biochar as an amendment in horticultural crops. However, their verification in the field is important for specific recommendations.  相似文献   

3.
The current study was carried out at Agricultural College, University of Baghdad in the vegetable farm, Department of Horticulture during 2013 spring growing season. Yield response to irrigation of different crops is of major importance in production planning where water resources are limited. This study aims to determine the effect of different irrigation treatment (deficit irrigation) and potassium humate fertilizer on yield, content of nitrogen, potassium, and phosphor in tuber of potato and water use efficiency in the Abu-Graib Region, Iraq. Potato was grown under drip irrigation with three treatments: irrigation applied when evaporation 75%, 100% and 125% from pan A, and three potassium humate fertilizers: 0, 1.2 and 2.4 kg/ha with three times additions. The seasonal potato evapotranspiration ranged from 267 mm to 372 mm. The drip irrigation treatment had significant effecting tuber yield of potato recorder 29,530, 27,630 and 24,880 kg/ha for 125%, 100% and 75% from pan A evapotranspiration, respectively. Humus fertilizers addition has the lowest value of ETa 309 mm and maximum value of yield 2,930 kg/ha. Water use efficiency (WUE) and irrigation water use efficiency (IWUE) values increased with increasing humus fertilizers, recording 9.92, 14.52, 8.59, 12.42 and 7.51, 10.70 kg/m3 for potassium humate K3 (2.4 kg/ha), K2 (1.2 kg/ha) and KI (0.0 kg/ha), respectively. Plants irrigated with 125% from class pans A evaporation, produced a significant increase in N, P and K content in tubers recorder 0.96%, 0.58% and 1.52%, respectively. Potassium humus-fertilizer significant differences among K1, K2 and K3 on high of plants reached 41.52, 50.08 and 56.39 cm, respectively, number of stems/plant 2.69, 3.22 and 3.78, respectively, leaves area index recorder 2.80, 3.35 and 3.73.  相似文献   

4.
【目的】研究马铃薯甲虫田间定殖与种群消长动态,为马铃薯的科学防治提供参考和依据。【方法】系统调查乌鲁木齐市西山农牧场和三坪农场马铃薯生长期,田间马铃薯甲虫种群消长规律,分析比较田间不同空间位置寄主植物上马铃薯甲虫种群数量,确定定殖时间与迁移过程。【结果】西山农牧场和三坪农场马铃薯甲虫定殖规律为:寄主作物田外马铃薯甲虫成虫出土后,最初迁移抵达寄主田块边缘,随后逐步向田块中心扩散,直至覆盖整个田块;马铃薯甲虫种群数量与定殖时间呈负相关,定殖时间越早,马铃薯甲虫种群数量越大;马铃薯甲虫种群数量与定殖点距离有一定的关系,在马铃薯甲虫定殖的早期,马铃薯甲虫与定殖距离呈负相关,定殖距离越大,马铃薯甲虫种群数量越小;随后两者的相关性逐渐降低,在后期两者呈正相关。【结论】马铃薯甲虫的定殖时间和定殖位置均会对其种群数量产生影响,应在田块边缘区域开展越冬代马铃薯甲虫成虫的早期监测,有效确定轮作田块内马铃薯甲虫种群的定殖与迁移过程。  相似文献   

5.
大西洋和费乌瑞它马铃薯品种的核型分析   总被引:2,自引:0,他引:2  
为了探索大西洋和费乌瑞它马铃薯品种的细胞遗传学特征,采用去壁低渗法对两品种的核型进行分析。结果表明:1)大西洋和费乌瑞它马铃薯品种都属四倍体,2n=48。2)大西洋的臂比值为(1.00±0.11)~(1.89±0.23),染色体相对长度为(5.07±0.79)%~(13.80±1.56)%,最长染色体/最短染色体=2.32,属于1B核型,核型公式为2n=4x=48=7m+2sm+2M+st;费乌瑞它的臂比值为(1.43±0.17)~(2.12±0.56),染色体相对长度为(6.04±0.54)%~(12.90±0.79)%,最长染色体/最短染色体=2.13,属于2B核型,核型公式为2n=4x=6m+5sm+t。  相似文献   

6.
The objective of this study was to evaluate the effects of elemental sulphur (S) and farmyard manure on soil pH, EC and N, S, P concentrations of tomato grown in a calcareous sandy loam soil. For this purpose, a pot experiment was conducted in greenhouse conditions. Sulphur was applied at 0, 50, 100, 150, 200, 400 mg kg~ and farmyard manure at 0, 3 ton da^-1 to the soil. Three weeks after applications, tomato seedlings were planted and 8 weeks later, the plants were harvested to determine N, S, P concentrations and dry matter yield. Soil pH and EC were determined in the soil samples taken at 3 different periods. Effects of sulphur and farmyard manure applications were not significant on N, P concentrations and dry matter yield of tomato plant. S concentration of tomato plant was increased by sulphur alone. Soil pH was decreased and soil EC was increased in both 2^nd and 3^rd soil sampling period by the sulphur applications. As a result of farmyard manure application, soil pH decreased in the 2^nd soil sampling period but increased in the 3^rd soil sampling period. Also, soil EC was significantly increased in 1^st and 3^rd soil sampling period. Farmyard manure had no significant effect on S supply to tomato plant. The N:S ratio of tomato plant was decreased by sulphur alone. However, the sulphur with farmyard manure applications decreased N:S ratio in lesser extend compared to the S applications.  相似文献   

7.
M.  M.  Adilov 《农业科学与技术》2010,(4):103-106
The results of the three-year researches which had the purpose to establish an optimum depth of seeding at sowing and rational norm of seeding of red beetroot seeds at under-winter sowing in conditions of mid-loamy typical grey soils of the central climatic zone of Uzbekistan are stated in article. The researches were spent at statement of field experiences in quadruple frequency with the area of a registration allotment 10 M^-1. Crops were carried out in the first decade of December against mulching surfaces of ridges by humus and without mulching. Crops were carried out on ridges in width of 70 sm tape-two-lined with distance between tapes of 50 sm, between lines-20 sm and distance between plants in a line of 12-13 sm, at density of standing of 228-230 thousand plants/hectares. Experiences were spent with zoned in Uzbekistan multi-seedling grade of a red beetroot "Bordo 237". Experiences were accompanied by phenological supervision, biometric accounts, the account of field germination of seeds, density of standing of plants and definition of size and quality of a crop. Results of researches were exposed to the statistical analysis by a dispersive method. It has been revealed that at under-winter sowing of a red beetroot the effective way providing acceleration of shoots occurrence, formations of high-grade density of standing and increase of productivity of root crops is mulching the surfaces of ridges by humus. It is defined that optimum depth of seeding at sowing both at application of mulching and without it is the depth of seeding 4 sm. It is established that the most rational norm of seeding of the seeds, providing high-grade density of standing, is at cultivation with application of mulching 8 kg/ha, and at cultivation without mulching 8-10 kg/ha. Application of mulching the surfaces of ridges by humus, depths of seeding of 4 sm and norms of seeding of seeds of 8-10 kg/ha in conditions of under-winter sowing in comparison with cultivation without mulching and depth of seeding 2 sm and norms of seeding of 6 kg/ha provides an acceleration of receipt of fresh production of a red beetroot for 12-14 days and considerably raises root crops productivity. Application of agro receptions improved by us is the important reserve of acceleration of receipt of red beetroot early production and increase of its manufacture.  相似文献   

8.
We represent assessment of the rats control operator's actions, starting from the placement of rat control means (chemical, mechanical and others) in the object territory until the full its elimination and followed by assessment of the probability of rat population recovery. The probability of success is evaluated when using a combination of rat control means. We took into account changes in rat population occurring in different calendar periods of the year. The proposed calculation method can be used in training programs, as well as for the local forecast of releasing objects from rats and rats' re-settling.  相似文献   

9.
Using scanning electron microscopy, we investigated the distribution of the trichoid, basiconic, and coeloconic sensilla on the antennae of the diamondback moth (DBM;Plutella xylostella). The trichoid sensilla were the most abundant sensory organ, and the male moth antennae host signiifcantly more trichoid sensilla than female moth antennae. Conversely, basiconic and coeloconic sensilla were found more frequently on female than on male antennae. We performed experiments with various degrees of antennal ablation and demonstrated that DBM antennae played a key role in the control of mating and oviposition. We found that neither oviposition preference nor mating behaviors changed signiifcantly when less than 1/4 of both antennae were removed. However, there was a signiifcant behavioral change when the antennae were ablated by more than half. As the length of the antenna was shortened, the successful mating rate decreased and mating peak was delayed. An otherwise consistent host preference for oviposition was eliminated when both antennae were completely removed. Furthermore, we found that the number of trichoid sensilla was positively correlated with mating rate and oviposition preference. However, the numbers of basiconic and coeloconic sensilla were not correlated with mating rate and mating peak, but highly correlated with oviposition preference. Taken together, our results indicate that antennal sensory information plays a critical role in the mating and oviposition behaviors of this economically important pest.  相似文献   

10.
Biochar is a potential micro-environment for soil microorganisms but evidence to support this suggestion is limited. We explored imaging techniques to visualize and quantify fungal colonization of habitable spaces in a biochar made from a woody feedstock. In addition to characterization of the biochar, it was necessary to optimize preparation and observation methodologies for examining fungal colonization of the biochar. Biochar surfaces and pores were investigated using several microscopy techniques. Biochar particles were compared in soilless media and after deposition in soil. Scanning electron microscopy (SEM) observations and characterization of the biochar demonstrated structural heterogeneity within and among biochar particles. Fungal colonization in and on biochar particles was observed using light, fluorescence and electron microscopy. Fluorescent brightener RR 2200 was more effective than Calcofluor White as a hyphal stain. Biochar retrieved from soil and observed using fluorescence microscopy exhibited distinct hyphal networks on external biochar surfaces. The extent of hyphal colonization of biochar incubated in soil was much less than for biochar artificially inoculated with fungi in a soilless medium. The location of fungal hyphae was more clearly visible using SEM than with fluorescence microscopy. Observations of biochar particles colonized by hyphae from soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and inside pores. Extensive hyphal colonization of the surface of the biochar in the soilless medium contrasted with limited hyphal colonization of pores within the biochar. Both visualization and quantification of hyphal colonization of surfaces and pores of biochar were restricted by two-dimensional imaging associated with uneven biochar surfaces and variable biochar pore structure. There was very little colonization ofbiochar from hyphae in the agricultural soil used in this study.  相似文献   

11.
The experiment was conducted during the short dry and the short rainy seasons in 2008. A botanical inventory and relative frequencies of forage selected by Djallonke sheep grazing were developed by observation and hand-plucking. Chemical composition and in vitro organic matter digestibility (IVOMD) of hand-plucked material was determined. From July to October, woody plants are a major component of the sheep diet. Sheep selected 40 woody plants and 21 species of herbaceous. During the dry season, grazing occurred more frequently in the fallows. The most frequent woody species belonged to Elaeis guineensis and Fagara zanthoxyloides. At the rainy season, a high proportion of Panicum maximum and Eleucine indica were sampled. Crude protein was high in woody leaves at the dry season. Crude fibre were more variable in herbaceous than in woody and herbaceous were generally higher in the levels of fibre. Chromolaena odorata, Citrus sinensis, Vitex doniana were very high in IVOMD. Spondias mombin, Moringa oleifera, Persea americana, Psidium guajava, Dialium guineense presented lowest values in IVOMD. Among herbaceous, Andropogon gayanus and Panicum maximum still presented a high value of IVOMD at the dry season. High proteins suggest woody with potential as nitrogen supplements to ruminants fed low quality forage during the dry season.  相似文献   

12.
The study area is located in a Mediterranean region, so the effects of the climate variations are very important. The authors contribution to this subject is based on the compilation of many results obtained from dissertations and theses that are carried out under their supervision. The main tool used, in addition to other methods, is the water hydrochemistry as it is proved very useful in obtaining good results and helpful in getting objective interpretations regarding the presence and absence of salinity. Several factors are undertaken to show the presence of salts in waters in the plain, the lithology of the geological formations shows that they are composed of alluvium sediments where the permeability is quite high, and this enables hydraulic communication between the fresh water of the aquifer and saline water of the sea. The study of climate shows a decrease of precipitation which favors an important decrease of recharge rate to the aquifer, and hence a decrease of water resource. The strontium which is a good indicator for the origin of salinity shows a variation that indicates a variation in the distribution of the salinity, and therefore diverse origins of salinity all over the studied area. This can infer the presence of marine invasion in the down-stream part of the aquifer, whereas elsewhere salinity is caused by the presence of evaporitic formation, mainly by the argillaceous matrix in the bottom of the lake. in the up-stream part of the aquifer. In the lake, salinity is explained  相似文献   

13.
The results of researches aimed to establish the optimum growing space and density of standing of plants at cultivation of cauliflower seeds in Uzbekistan are stated in the article. Researches were spent in the suburb of Tashkent with a mid-early grade "Domestic". In experiences were compared 5 densities of standing (31746, 35714, 40806, 47620 and 57142 pieces/hectare) received at planting of sprouts with row-spacing of 70 sm and distance between plants in a row 25, 30, 35, 40 and 45 sm. Experiences were pawned in quadruple frequency with the area of an allotment 10 M2. 60-65 day sprouts were planted under film tunnel shelters on February 11-12. Film shelters were kept over plants till the end of March. Seed plants were grown up without formation. Experiences were accompanied by phonological control, calculation of leaves quantity, an establishment of average weight of a head, definition of quantity of the plants, which have given seeds, the account of a crop of seeds from a bush and of a unit of area. It has been defined that reception of seeds of a cauliflower at cultivation under film tunnels is quite possible in Uzbekistan. It is established that with representation of the big growing space the plants form more leaves, earlier and larger form the heads, develop the testicles acceleration and increase their seed efficiency. It has been revealed that the more plants thickness is, the bigger share of them does not give seeds. In this connection the greatest crop of seeds has been received at growing space 70x45 sm at which 31.7 thousand Pl/ha had been planted. It is proved that in the conditions of Uzbekistan it is possible to cultivate high-grade seeds of cauliflower with productivity of 127-147 kg/ha.  相似文献   

14.
The quality office is complex and made up of many components such as nutritional quality, appearance, cooking quality and eating quality. The cultivar is one of the main factors that could affect to the grain quality office. The aim of this work was to analyze and compare the cooking quality parameters of six different japonica varieties of rice grown in Spain (Senia, Gleva, Bahia, Maratelli, Guadiamar and Bomba). This work focused on the study of the cooking quality of rice, because it is one of the most important factors related to grain quality in Spain. It was evaluated using five characteristics: amylose content, gel consistency, degree of spreading, gelatinization temperature and pasting parameters. The amylose content ranged from 11.60% to 21.46%, with the Gleva cultivar having the lowest amylose content and with Bomba having the highest. The gel consistency varied between 5.44 cm and 9.81 cm. Regarding the alkali test, the Maratelli cultivar had the highest dispersion and transparency. Maratelli had the lowest gelatinization temperature (61.67±0.08 ℃), and Senia had the highest gelatinization temperature (67.05±0.02 ℃). Finally, the pasting parameters showed significant differences among cultivars with different viscosities.  相似文献   

15.
It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6°C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3℃ temperature increase on a complete generation of the brown planthopper (Nilaparvata lugens) on rice (Oryza sativa). Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper (BPH) nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a signiifcant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size.  相似文献   

16.
The residual effect of organic and mineral fertilizers on selected chemical properties of an Alfisol in the long term soil fertility trial established in 1950 at Samaru, Nigerian savanna was assessed. The trial was left fallow for fourteen years due to lack of funds. Topsoil was collected from plots that received three levels of cow dung (D), nitrogen (N) and phosphorus (P) in all possible combinations. The soils were analyzed for selected chemical properties. Except for significant effect of applied P on available P, sole application of cow dung, N or P had no significant effect on all the measured soil properties. The interaction of D and P significantly affected the mean values of exchangeable Ca, Mg, K and ECEC in the range of 1.12-1.96, 0.62-1.11, 0.37-0.64 and 2.82-4.11 cmol/kg respectively. The most important results were the ability of the plot that received neither D nor P to significantly increase these parameters than the plots that received only one of the treatments. The results show that the fallow period has changed the effects of application of organic and mineral fertilizers on the soil chemical properties under continuous cultivation by modifying them towards those of a native savanna Alfisol.  相似文献   

17.
The responses of five inter-specific lowland rice cultivars (NERICA-L-19, NERICA-L-20, NERICA-L-41, NERICA-L-42, and NERICA-L-60) and four improved Oryza sativa cultivars (FKR 19, BW 348-1, WITA 4, and SIPI 6923033) to levels of phosphorus and nitrogen fertilization were compared on a Typic Natrustalfat Kadawa in the Nigerian Sudan Savanna in 2006 and 2007 The responses of the NERICA-L eultivars to N and P fertilization were similar to the O. sativa cultivars. In a dry year (2007), the NERICA-L cultivars gave higher yields than O. sativa cultivars. Phosphorus level did not significantly affect crop physiology, yield, and yield components of all the cultivars. Pooled across cultivars, N and P levels, days to panicle initiation, mid-flowering and maturity were, respectively delayed by 17.0, 15.6 and 6.4 days in 2007 compared to 2006. NERICA-L-42 and NERICA-L-41 were the most stable, exhibiting the least difference in duration to maturity between the two years (3.5 and 4.4 days, respectively), and could therefore be more adapted to rain-fed environments prone to frequent droughts. Increasing N levels from 0 to 120 kg hal produced yield increments of 62.9 and 37.2% in 2006 and 2007, respectively. Cultivars FKR 19 and WITA 4 gave higher yields in 2006 (3940 and 3542 kg ha^-1, respectively), while in 2007, NERICA-L-42, NERICA-L^-19 and NERICA-L-20 ranked among the highest in grain yield (3935, 3807 and 3726 kg hal, respectively) and could be recommended to resource-poor farmers. a  相似文献   

18.
The effects of different tillage systems and poultry manure on soil physical properties, performance and nutrients in sorghum were studied for three years at Owo, southwest Nigeria. There was factorial combinations of herbicide-based zero tillage (ZT), manual clearing (MC), disc ploughing (P), ploughing plus harrowing (P+H) and ploughing plus double harrowing (P+2H), and two rates of poultry manure at 0 and 7.5 Mg ha^-1. Herbicide-based zero tillage and manual clearing reduced soil temperature and conserved more water than mechanized tillage techniques. Poultry manure reduced soil bulk density and temperature and increased soil water and porosity. There was a percentage decrease of leaf N, P, K, Ca and Mg concentrations, plant height, leaf area, stem girth, root dry weight, dry matter and grain yield in ascending order for herbicide-based zero tillage, manual clearing, ploughing, ploughing plus harrowing and ploughing plus double harrowing while percentage increases were recorded in a descending order for all the various combinations of tillage with poultry manure in that order. Poultry manure in combination with tillage increased dry matter and grain yield by 33.1 and 39.5%, respectively in comparison with tillage only. The manure-zero tillage methods increased dry matter and grain yield by 8% and 15%, respectively when compared with manure-mechanized tillage methods. Zero tillage or manual clearing in combination with 7.5 Mg ha^-1 poultry manure was most suitable for sorghum cultivation.  相似文献   

19.
Leafhopper Cicadulina bipunctata is represented the main insect as a pathogen for phytoplasma disease occurring by insect-transmitted plant viruses in date palm orchards. Therefore, it is important to investigate the potential effect of some insecticides against such insect. The adults of leafhopper C. bipunctata were collected from date palm orchards in Alhasa, Eastern province, Saudi Arabia. Three insecticides from different classes--beta-cyfluthrin (pyrethroids), imidacloprid (neonicotinoids) and abamectin (natural compounds)--have been evaluated in vivo against adults C. bipunctata. This stage was exposed to residual film of various concentrations of each insecticide on transparent plastic cups using a Potter precision laboratory spray tower. Bioassay test showed that both beta-cyfluthrin and imidacloprid caused 100% mortality by 500 ppm at 24 h after treatment, whereas abamectin gave the same mortality by 50 ppm at the same time. Toxicity values revealed that abameetin was the most potent insecticide compared with beta-cyfluthrin and imidacloprid, where the lethal concentrations LC50 and LC95 were 24.58 ppm and 116.73 ppm at 3 h after treatment, respectively. Therefore, abamectin can be a possible candidate to be applied on date palm or ground grass by the Ministry of Agriculture after successful field experiments.  相似文献   

20.
E.  O.  Idowu 《农业科学与技术》2011,(4):472-475
The protein, carbohydrate and lipid contents of the food ingested and their absorption in the intestine ofHepsetus odoe in Ado-Ekiti Reservoir, Ekiti State, Nigeria were investigated. Samples were analysed chemically for protein, fat and carbohydrate using the official methods of analysis described by the Association of Official Analytical Chemist. The ingested food had mean total protein, mean total carbohydrate and mean total lipid of 60.2% - 8.55%, 15.4% ± 1.9% and 15.6% ±1.1% of the organic content respectively. Calculated mean total percentages absorbed were 72.4% protein, 52% carbohydrate and 51.5% lipid. The foregut had the highest percentage absorption while the hindgut had the lowest for all the nutrients. Different sizes of fish showed different dietary protein, carbohydrate and lipid contents. Absorptive capacity for these components of the food also varied with fish size.  相似文献   

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