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1.
《Crop Protection》1987,6(5):289-294
In the early and late cropping seasons of 1983, three different methods of tillage (minimum tillage, conventional tillage, and tilled and ridged) were evaluated for their influence on the performance of some pre-emergence herbicides used during the production of cowpea. Four varieties of cowpea (Ife Brown, H 144-1, TVx 3236, and Black-eyed bean) were planted in the early season while five varieties (Ife Brown, H 144-1, TVx 3236, H64/3 and Vita-5) were planted in the late season. A single spray application of 3·0 kg/ha alachlor, 3·0 kg/ha metobromuron + metolachlor and 3·5 kg/ha metolachlor was carried out one day before planting. Cyanazine at 3·0 kg/ha was included in the late season trial. The plots were either minimally tilled, conventionally tilled or tilled and ridged at the Teaching and Research Farm of the University of Ife. Results showed that the performance of all three herbicides used in the early season, as measured by weed control and grain yields, was best on the conventionally tilled, while the performance of the four herbicides in the late season was best on tilled and ridged plots. Metobromuron + metolachlor performed consistently better than each of the other herbicides irrespective of the method of tillage during both seasons. Conventional tillage enhanced the performance of metobromuron + metolachlor over minimum tillage plots and tilled and ridged plots in the early season; however, in the late season, the performance of metobromuron + metolachlor was best on tilled and ridged plots. Alachlor did not effectively control competing weeds in both seasons but did not injure any cowpea line. On the other hand, cyanazine did not control weeds effectively but was phytotoxic to Ife Brown variety of cowpea. In both seasons, the control of the broad-leaved weeds Ageratum conyzoides, Amaranthus spp., Euphorbia heterophylla, Ipomoea spp., Spigelia anthelmia, Synedrella nodiflora and Talinum triangulare was not adequate. The control of the grassy weeds Brachiaria deflexa, Cynodon dactylon, Imperata cylindrica and Eleusine indica was, however, effective.  相似文献   

2.
The chemical composition and functional properties of ungerminated and germinated seeds of four advanced lines of cowpeas (IT81D-699, IT82E-18, IT84S-2246-4 and TVx 3236) were investigated. Ungerminated seeds contained 20.1 to 25.8% crude protein, 2.0 to 2.2% lipid, 115.1 to 210.0 mg phyticacid/100 g and 8.9 to 9.6 mg iron/100 g. The polyphenol contents of the brown- and cream-colored beans were similar (192.0 to 196.0 mg/100 g) but were significantly (p<0.05) higher than the amount (99.8 mg/100 g) found in the white beans. Germination increased the crude protein content, total phosphorus content, nitrogen solubility, fat absorption capacity and foam capacity but decreased ether extract, polyphenol and phytic acid contents, water absorption capacity, bulk density and foam stability of all cowpea lines. Incorporation of up to 0.2 M NaCI improved foam volume. Ungerminated seeds had high water (2.3–3.2 g/g) absorption capacities, while germinated seeds had high fat (3.1–3.6 g/g) absorption capacities. TVx 3236 and IT81D-699 might be selected for combining such characteristics as high crude protein, low phytic acid content and good foaming properties into a single cowpea line through breeding.  相似文献   

3.
Insect pests are a major constraint to cowpea production in Africa. Therefore the aim of this study was to identify cowpea material that exhibit greater pest resistance and grain yield for evaluation by farmers. About 45 cowpea genotypes were assayed for flavonoids and anthocyanins with the objective of quantifying the levels of these phenolics in seed extracts as markers for effective plant defence. The results revealed significant differences in the concentration of flavonoids and anthocyanins in seed extract. Farmer varieties such as Sanzie, Bensogla and Omondaw exhibited much higher levels of phenolics compared with improved genotypes like ITH98-46, TVu1509 and IT93K-452-1. When planted in the field in Ghana and Tanzania, the genotypes that had high concentrations of flavonoids and anthocyanins in seed extracts (e.g. Bensogla, Omondaw and IT86D-2075) showed relatively lower infestation by thrips, pod-sucking bugs, aphids and alcidodes. Providing minimum protection with insecticide spray further showed that, genotypes with low infestation by thrips and pod-sucking bugs produced more grain yield without spraying, an indication of their natural resistance to these insect pests. Furthermore, farmer-selected varieties such as Sanzie, Bensogla, and Omondaw produced more grain yield without protection than their improved counterparts. These results showed that the higher the concentration of flavonoids and anthocyanins in cowpea seed extracts, the lower the insect pest incidence on seedlings raised from those seeds. Correlation analysis further confirmed a direct relationship between high flavonoids/anthocyanins in seed extracts and enhanced insect pest.  相似文献   

4.
Reports on the nutritional composition of cowpea leaves have been limited to a small number of lines and the palatability characteristics of leaves apparently have not been studied. This study was therefore undertaken on cowpea leaves to determine the nutrient composition of fifteen varieties and the sensory attributes of ten varieties grown in Ghana. Nutritional components studied were moisture, protein, phosphorus and ascorbic acid. The sensory attributes included leaf size, taste and overall acceptability. There were significant (p > 0.05) differences among varieties in all nutrient components (fresh and dry weight basis), leaf size and overall acceptability. The nutrient composition values, on a dry weight basis, ranged from 9.4 to 13.0% for moisture, 303.8 to 468.9 mg/100 g for phosphorus, 33.5 to 148.0 mg/100 g for ascorbic acid, and 27.1 to 34.7% for protein. Differences in the sensory scores of leaves for taste were not significant (p < 0.05). Overall acceptability positively correlated with leaf size. Moisture content was negatively correlated with overall acceptability, phosphorus and ascorbic acid. Results can be exploited in a breeding program to develop nutritionally superior and acceptable cowpea varieties which can be used for harvesting of both leaves and seeds.  相似文献   

5.
An economic analysis on the use of herbicide to control weeds in garlic production in 2002/2003 and 2003/2004 dry seasons indicated a considerable reduction in the cost of weed control and labour demand with the application of herbicide. Although the hoe weeding and the herbicide gave comparable bulb yield in 2002/2003 dry season, the net return per hectare was higher with herbicide application in both seasons. Similarly, the value of labour saved through herbicides use was positive throughout and increased significantly in 2003/2004 dry season.  相似文献   

6.
Chemical and nutritional characteristics of irradiated and nonirradiated cowpea bean at 0.2 kGy submitted to several thermal treatments were studied. The cowpea bean flours irradiated at 0.2 kGy were superior to those non-irradiated concerning digestibility and the flours submitted to microwave oven were superior to those cooked under low pressure, autoclaved or even raw from the nutritional point of view. As to the presence of anti-nutritional factors, the results showed that the variety of cowpea bean under research presented neither trypsin inhibitor nor haemagglutinin activity, however, regarding tannin, a 0.006% content was found and considered negligible.  相似文献   

7.
The quality of the cowpea bean protein was improved through supplementations with flours from beans exposed to microwave oven treated with cereal proteins such as wheat, rice, corn, and sorghum. Biological assays results with these blends showed that the casein exceeded the other diets concerning digestibility only; however, in parameters such as biological value, net protein utilization (NPU), protein efficiency ratio (PER) and nutritional efficiency ratio (NER), no significant differences occurred. Among all elaborated blends, the one with irradiated beans submitted to microwave oven for 30 minutes (65%) + rice (35%) presented the best results. The soup elaborated with the best supplemented blend was satisfactory concerning color, odor, flavor and texture.  相似文献   

8.
Saflufenacil is a new herbicide being developed for pre-plant burndown for non-selective removal of broadleaf weeds and pre-emergence (PRE) broadleaf weed control in field crops, including maize, soybean, sorghum and wheat. As part of studying the potential use pattern of this herbicide, four field studies were conducted in 2006 and 2007 at Concord, northeast Nebraska, to determine winter wheat tolerance to PRE and post-emergence (POST) applications of saflufenacil. The fall POST applications were conducted at the 2–3 leaf stage (5 cm height) whereas the spring POST and tank-mixes studies were sprayed at the 4th node stage (40 cm height) of crop. Dose-response curves based on log-logistic model were used to determine the ED (effective dose) values of saflufenacil for visual ratings of crop injury and relative yield. There was no crop injury or yield reduction with PRE applied saflufenacil dose of up to 400 g a.i. ha−1. However, there was significant crop injury in the POST applications in the fall (up to 95%) and in the spring (up to 67%). There was also yield reduction of as much as 66% in the fall and 58% in the spring POST applications. Addition of adjuvants also increased crop injury levels. For example, at 14 days after treatment in the fall applications, about 5% visual crop injury (ED5) was evident with 82, 67 and 10 g a.i. ha−1 of saflufenacil compared with 51, 30 and 11 g a.i. ha−1 in the spring, with no adjuvant, or non-ionic surfactant (NIS), or crop oil concentrate (COC), respectively. Saflufenacil at half the proposed used dose of 25 g a.i. ha−1 was safe to mix with the currently used POST herbicides of wheat with no visible crop injury and yield reduction. PRE applications of saflufenacil would be safe for use in winter wheat; however, the POST application of saflufenacil alone or with the adjuvant NIS or COC produces unacceptable injury and yield loss. These results are similar to the proposed PRE use pattern of saflufenacil. In addition, the proposed label does not suggest the POST use of saflufenacil in winter wheat, or any other cereal crops, which is similar to what we have concluded from this study.  相似文献   

9.
Saflufenacil is a new herbicide being developed by BASF for pre-emergence application for broadleaved weed control in maize and other crops. Three field studies were conducted in Ontario, Canada over a 2-year period (2006 and 2007) to evaluate the tolerance of spring cereals (barley, oats, and wheat) to pre-emergence and post-emergence applications of saflufenacil at 50 and 100 g ai ha−1. Saflufenacil pre-emergence caused minimal visible injury (1% or less) at 3, 7, 14 and 28 days after emergence and had no adverse effect on plant height or yield of barley, oats, and wheat. Saflufenacil plus the surfactant Merge (1% v/v) applied post-emergence caused as much as 76, 60, 52 and 35% visible injury in spring cereals at 3, 7, 14 and 28 DAT, respectively. Injury with saflufenacil plus Merge applied post-emergence decreased over time and was generally greater as dose increased. Saflufenacil plus Merge applied post-emergence reduced plant height by as much as 16% and reduced yield of spring barley and wheat by 24 and 13%, respectively, but had no effect on the yield of spring oats. Based on these results, saflufenacil applied pre-emergence at the proposed dose can be safely used in spring planted barley, oats and wheat; however, the post-emergence application of saflufenacil results in unacceptable injury and yield loss. These results are consistent with the proposed pre-emergence use pattern for saflufenacil.  相似文献   

10.
The effect of weed control treatments for long season control of weeds in maize under zero and minimum tillage was evaluated at Samara in northern Nigeria. Among the weed control treatments evaluated, soil ridging plus application of either 2,4-D or atrazine at 1.5 kg a.i/ha performed well as they effectively controlled weeds and resulted in better growth and a grain yield that was comparable to the hand weed control. Maize production under minimum tillage was better than under zero tillage.  相似文献   

11.
This work aimed to study the induction of defence proteins in cowpea seedlings during the first days after infection with the fungi Fusarium oxysporum f. sp. cubenses and F. oxysporum f. sp. phaseoli. Cowpea seeds, after disinfection, were transferred to Petri dishes containing 0.5% agar and, after germination, were infected with a drop of a suspension containing 0.5 × 104 spores ml−1. Seedlings were collected at 24, 48, 72 and 96 h after infection and were dissected into leaves, hypocotyls, roots, cotyledons and teguments, which were measured and weighed for morphometric analysis. The agar medium was also analyzed. Enzymatic assays of proteic extracts yielded antimicrobial peptides detected by Western blotting. The cowpea seedlings showed a complex pattern of induction and repression of defence proteins in response to infection by both pathogens. Furthermore, morphometric analysis showed differences between infected and control seedlings. Infected samples did not at any time exhibit chitinase activity, but did exhibit different β-1,3-glucanase and peroxidase activities. Western blotting for lipid transfer protein (LTP) demonstrated its presence in all parts of the infected seedlings. Exuded proteins, also obtained from cowpea seeds in the germination medium, were separated by SDS-PAGE and tricine gel electrophoresis. The analysis showed that some proteins were exuded from moistened cowpea seeds, particularly after F. oxysporum infection.  相似文献   

12.
Field trials were conducted at Samaru in the northern Guinea and at Bakuta and Kadawa in the Sudan Savanna ecological zones of Nigeria to identify suitable herbicides for weed control in irrigated onion. The herbicides tested were chlorthal-dimethyl, fluorodifen and oxadiazon. In the trials each herbicide treatment was compared with an identical treatment which received supplementary hand-weeding. The results of these experiments show that oxadiazon at 1·0–2·0 kg a.i./ha, with or without supplementary hoe-weeding at 6 weeks after transplanting, combined effective weed control with high bulb yields in irrigated dry season onions. While fluorodifen at 1·5 kg a.i./ha followed by supplementary hoe-weeding may be effective at sites with low weed infestation, a higher rate (3·0 kg/ha) may be desirable at sites with a higher broad-leaved weed infestation. Chlorthaldimethyl at 10·0 kg a.i./ha effectively controlled weeds at all the sites and gave high onion yields at sites with 6–12% clay; the selectivity was, however, lower at Bakura with very light soil. Uncontrolled weed growth caused 49–86% reduction in the bulb yields compared with the best herbicide treatments.  相似文献   

13.
A fuzzy-logic based model was built in order to assess the relative influence of different ecological and management drivers on glyphosate resistance risk (GRR) in Sorghum halepense (L.) Pers. The model was hierarchically structured in a bottom-up manner by combining 16 input variables throughout a logical network. Input data were related to 1) herbicide usage, 2) crop rotation, 3) landscape characterization, 4) weed dispersal, and 5) mean maximum and minimum seasonal temperature. Mean maximum and minimum seasonal temperatures and the dominance of glyphosate use were the variables that showed the highest sensitivity to input changes. Application of the model at a regional scale resulted in a wide range of GRR values. The lowest range values (lower than 0 and between 0 and 0.25) were represented in 5.5% and 21.5% of the cropping area, respectively. Intermediate GRR range (between 0.25 and 0.5) were assessed in 57.3% of the cropping area whilst the highest GRR range values (0.5–0.7) were represented in only 15.6% of the studied area. The assessment of trade-offs between different ecosystem functions through expert opinion can complement traditional analyses for predicting herbicide resistance risk based on solely the genetic aspect of the evolutionary process.  相似文献   

14.
Lolium multiflorum Lam. (annual ryegrass) is used extensively as a forage crop and seed is produced in several areas worldwide. Seed production has been shown to be commercially possible in Atlantic Canada but improved weed control is needed. Studies were conducted in two provinces (Prince Edward Island and New Brunswick) to determine the effects of the herbicides bentazon, bromoxynil/MCPA, dicamba/MCPA, thifensulfuron/tribenuron, 2,4-D and MCPA on weed control, L. multiflorum growth, seed yields and seed germination in 1998 and 1999. The herbicides MCPA, dicamba/MCPA and bromoxynil/MCPA as evaluated in these experiments provided acceptable control of the broad-leaved weeds present and had no effect on seed yield or seed germination. Although the thifensulfuron/tribenuron caused early foliar injury, the plants recovered and it provided excellent weed control. None of the herbicides affected seed germination. MCPA, dicamba/MCPA and bromoxynil/MCPA could be used to provide control of broad-leaved weeds and thifensulfuron/tribenuron could be used if growers were willing to accept some early injury and possible yield loss to obtain the improved weed control.  相似文献   

15.
Common bacterial blight disease of cowpea, caused by Xanthomonas axonopodis pv phaseoli, has been identified as the most important biotic constraint to cowpea production worldwide. Continuous and indiscriminate application of chemical pesticides has necessitated the search for an environment friendly method of control. Azadirachta indica (neem), Acalypha wilkisiana (red acalypha) and Carica papaya (pawpaw) extracts were field-tested against common bacterial blight disease. The experiment was laid out as a randomized complete-block design (RCBD) with three replicates. Cold extracts of 6.67% concentration of the plant leaves were sprayed on cowpea (variety ‘Ife brown’) foliage. Streptomycin sulfate of 0.2% concentration was applied as a positive control and sterile distilled water as a negative control. Incidence of common bacterial blight ranged from 20.00 to 43.74% and severity from 1.02 to 2.00 on a 1–6 scale, where 1 = no symptoms of common bacterial blight and 6 = necrotic lesions on more than 75% of the leaf area. A combination of extracts of pawpaw, neem and red acalypha reduced disease incidence by 73.68% and improved yield by 1.58 tons/ha (a 73.49% increase) compared with untreated control. Azadirachta indica, Acalypha wilkisiana and Carica papaya extracts, both singly and in combination (Pawpaw + neem + Acalypha, Pawpaw + neem, Pawpaw + Acalypha and neem + Acalypha), reduced incidence and severity of common bacterial blight disease and increased yield of cowpea. Thus, these plant extracts could serve as viable alternative to synthetic chemicals to control Xanthomonas-caused diseases in cowpea.  相似文献   

16.
Field and laboratory experiments were conducted in the early and late rainy seasons in Thailand to evaluate the effect of pre-emergence application of herbicides and determine the herbicide residues on vegetable soybean (Glycine max L. Merrill cv. No. 75) production. No visible crop injury was observed after application of alachlor 469 g a.i./ha, clomazone 1080 g a.i./ha, metribuzin 525 g a.i./ha, pendimethalin 1031.25 g a.i./ha, tank-mixed clomazone 960 g a.i./ha + pendimethalin 928 g a.i./ha, or tank-mixed metribuzin 350 g a.i./ha + pendimethalin 928 g a.i./ha. However, acetochlor 1875 g a.i./ha, isoxaflutole 75 g a.i./ha, and oxadiazon 1000 g a.i./ha caused visible crop injury. Plant bioassay of herbicide residues in the soil after harvest showed no phytotoxic effect on baby corn (Zea mays Linn. cv. Suwan 3), cucumber (Cucumis sativus L. cv. Pijit 1), pak choi (Brassica chinensis Jusl. cv. Chinensis), and soybean (G. max L. Merrill cv. CM 60). Gas Chromatography-Mass Spectrometry (GC–MS) analysis showed no significant herbicide residues on crop yield (or MRLs < 0.01 ppm) for all herbicides used in this study. The application of metribuzin at 525 g a.i./ha was sufficient to provide satisfactory full-season control of several weed species and gave the highest crop yield. In addition, pendimethalin at 1031.25 g a.i./ha, and tank-mixed metribuzin at 350 g a.i./ha + pendimethalin at 928 g a.i./ha can provide a similar level of weed control as an alternative to reduce herbicide dosage thereby increasing food and environmental safety in vegetable soybean production.  相似文献   

17.
Simple wet heat treatments like simple boiling (atmospheric pressure, 100 °C) and pressurized boiling (higher than 100 °C) reduced the polyphenol content of mature dark red seeds of cowpea (Vigna unguiculata (L.) Walp.) cultivar UPL Cp 3 by 61 to 80% and improved in vitro protein digestibility (IVPD) by 6 to 26%. Pressurized steaming (higher than 100 °C) removed 48 to 83% of the polyphenols but increased IVPD by only 1.1 to 4.2%. Dry heat as exemplified by roasting and microwave treatment inactivated 58 to 71% of the tannins but increased IVPD by only 1%. All the heat treatments were effective in removing/inactivating polyphenols though different responses were observed with the resulting in vitro protein digestibilities.  相似文献   

18.
Jason K. Norsworthy   《Crop Protection》2004,23(12):721-1235
A field study was conducted in 2001 and 2002 at Blackville, SC, to evaluate broadleaved weed control and economics of conventional and glyphosate-containing herbicide programmes in glyphosate-resistant soybean planted in 97-cm-wide rows. Treatments included chlorimuron plus sulfentrazone or chlorimuron plus metribuzin applied pre-emergence followed by post-emergence applications of lactofen or glyphosate 4 wk after soybean emergence (WAE). Other treatments were glyphosate applied 4 WAE, sequential applications of low dose glyphosate applied 2 and 4 WAE, and a non-treated control. Pre-emergence herbicides followed by glyphosate, controlled Ipomoea lacunosa L. 8 WAE. I. hederacea var. integriuscula Gray control with pre-emergence herbicides followed by glyphosate was 100% with similar control from chlorimuron plus sulfentrazone followed by lactofen, whereas control following the single glyphosate application was 84%. Amaranthus palmeri S. Wats. control 9 WAE was 100% following single or sequential glyphosate applications, while control ranged from 76% to 96% with pre-emergence herbicides followed by lactofen. However, early season weed interference when a single application of glyphosate was delayed until 4 WAE reduced soybean yields an average of 389 kg/ha compared to pre-emergence herbicides followed by glyphosate. Based on mean contrasts, pre-emergence herbicides followed by glyphosate had greater gross profit margins than a single glyphosate application alone, but were similar to sequential glyphosate applications. Gross profit margins from pre-emergence herbicides followed by lactofen were not different from glyphosate alone.  相似文献   

19.
The baobab milk and fermented baobab/acha flour mixtures were analyzed chemically for their proximate, ascorbate, mineral and antinutrient composition. The dry pulp scraped from baobab fruits was kneaded, made into solution, extracted through cheese-cloth and stored frozen until analyzed. The acha and baobab grains were cleaned, fermented for 24 to 120 hours, dried and hammermilled into fine flours. The unfermented flours served as controls. The standard assay methods of AOAC were selected for use for the analysis of the nutrients and the antinutrients. The mixtures were composed of 70% acha and 30% baobab flours (70:30 protein basis). The baobab milk contained more protein (1.5%) and minerals (Fe, 17.8 mg; Ca 134.2 mg) than those of human milk (protein, 1.3%, Fe, 0.2 mg, Ca 30 mg) and cow milk (Fe, 0.1 mg; Ca 1.20 mg) and most leading national commercial infant formulas e.g. cerelac (Fe, 10.0 mg). The composite flours contained more nutrients than the baobab or the acha flour alone. The BF96 had greater advantage over other BF flours as a supplement to acha. The mixtures are within the reach of lower income group and can be incorporated into their diets.  相似文献   

20.
Field studies were conducted at two sesame-growing regions of Texas in 2004 and 2005 to determine weed control and sesame response to four dinitroaniline herbicides and their method of incorporation. Ethalfluralin, pendimethalin (formulated as Prowl EC), and trifluralin were applied at the X, 1X, and 2X of the suggested label dose for Gossypium hirsutum L. Pendimethalin (formulated as Prowl H2O) was applied at the X, 1X, and 1X rate. Two methods of incorporation included rolling cultivator mixing wheels and spring tooth harrow. With rolling cultivator mixing wheels, all herbicides controlled Amaranthus tuberculatus (Moq.) J.D. Sauer at least 74% regardless of dose. The X dose of ethalfluralin and pendimethalin (formulated as Prowl EC), or the X and 1X dose of pendimethalin (formulated as Prowl H2O) controlled Brachiaria platyphylla (Griseb.) Nash no better than 73% while all other doses of the herbicides controlled B. platyphylla at least 80%. The use of mixing wheels to incorporate the herbicides resulted in better sesame stands and less stunting than the use of the spring tooth harrow; however, sesame stands were reduced as herbicide rate increased when using mixing wheels. Ethalfluralin at the 1X dose, pendimethalin (formulated as Prowl H2O) at the X dose, and trifluralin at the X dose produced the highest sesame yield while ethalfluralin at the 2X dose produced the lowest yield.  相似文献   

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