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31.
Xiaodong Chen Yaa Opoku-Kwanowaa Jianming Li 《Communications in Soil Science and Plant Analysis》2020,51(9):1238-1252
ABSTRACT
Soil available nutrients and soil salt ions are considered to play a significant role in soil fertility. A two-year field experiment was conducted to investigate the effects of different agricultural organic wastes on soil available nutrients and soil ions in a primary saline soil, located in the west of Jilin Province, China. The treatments were granular corn straw (GS), coarse corn straw (CS), sheep manure (SM), fodder grass (FG), and control (CK). The results showed that agricultural organic wastes effectively decreased soil pH by 1.28%-3.83%. The application of agricultural organic wastes also improved soil available nutrients, of which the available nitrogen (AN) increased by 23.64%-32.54%, the available phosphorus (AP) increased by 16% ?19.93%, and the available potassium (AK) increased by 2.78% – 8.42%. In contrast, the content of soil salt ions decreased significantly with the exception of potassium ions. Linear dependence suggests that, with the decrease of soil pH, the soil available nutrient content was higher. From the correlation analysis, the relationship between other salt ions and soil available nutrients showed an extremely significant negative correlation with the exception of potassium (K+). The redundancy analysis (RDA) showed that calcium (Ca2+) and potassium (K+) are the main factor affecting soil available nutrient content in 2a (about 12 months after organic wastes were applied) and 3a (about 24 months after organic wastes were applied), respectively. In conclusion, treatment GS is recommended for improving soil available nutrients and decreasing the pH and content of soil salt ions in primary saline-alkali soils. 相似文献
32.
Emmanuel Amoah Boakye Dibi N’da Hyppolite Victor Rex Barnes Stefan Porembski 《Arid Land Research and Management》2017,31(2):219-233
Understanding the impacts of agricultural land use is desired for proper management of riparian forests buffers (RFs) in savannas. In this light, we analyzed the relationship between woody plant diversity and soil properties of RFs in farmlands (FAs) and protected areas (PAs) along Afram (Guinean zone) and Tankwidi (Sudanian zone) Rivers located within the Volta sub-basin of Ghana. ALOS-AVNIR imageries were used to map RFs to facilitate sampling of soil and woody vegetation (dbh ≥5?cm) using stratified randomized design (72 plots; size: 500?m2 each) for the analysis of soil physical and chemical properties and Shannon-Wiener plant species diversity. Although the fractions of sand, silt, and clay varied between the PAs and FAs, they were predominantly categorized as sandy loam. Along the Afram River, there were no significant differences in the concentrations and nutrient stocks of soil C, N, P, and K as well as the pH, moisture content, and bulk density between PA and FA. For the Tankwidi River, the concentrations and nutrient stocks of C and K significantly decreased from PA to FA while N, P, pH, bulk density, and moisture content were not different. Of the soil attributes measured C, N, P, pH, ground slope, and soil moisture had significant relationships with the diversity and density of the riparian woody plants. Controlling agricultural activities in riparian forests could preserve soil properties similar to that found in protected areas. 相似文献
33.
The objective of this experiment was to determine the effects of preslaughter isolation and feed withdrawal duration on physiological responses and shrinkage in goats. A total of 84 Spanish does (36 mo of age, average weight 35 kg) were individually weighed and scored for excitability before two replicate (day) trials. The does were feed-deprived (FD) or fed (F) in holding pens (treatment, TRT) for either 0, 7, 14, or 21 h (TIME). At the end of the holding periods, FD and F does were blood-sampled (n = 6 does/treatment/time/replicate) and weighed again to assess physiological responses and shrinkage, respectively. Individual does from each pen were blood-sampled again after imposing one of three handling post-treatments: a 15-min isolation with no visual contact with other does (I); a 15-min isolation with visual contact (IV); or no isolation (C, control). Plasma cortisol concentrations were higher at 0 h than at other holding time periods (P < 0.01). Plasma triiodothyronine, thyroxine, and leptin concentrations, and differential leukocyte counts were not influenced by any of the factors. The rate of decline in glucose concentrations over TIME was greater in FD than in F group (TRT x TIME, P < 0.05). The overall plasma creatine kinase activity peaked at 7 h before reaching a lower level at 14- and 21-h holding (P < 0.05). Plasma urea nitrogen concentrations were higher at 0- and 21-h than at 7- and 14-h holding (P < 0.01). Plasma nonesterified FA concentrations in the FD group remained at an elevated level during holding, but in the F group the levels decreased at 7 h and remained at that level (TRT x TIME, P < 0.01). Excitability scores did not have any effect on the variables measured. Shrinkage increased with longer holding time, but more prominently in the FD group (TRT x TIME, P < 0.01). Plasma cortisol concentrations were greater in I and IV groups than in the C group (P < 0.01). The novelty of environment during preslaughter holding, and social isolation may be more potent stressors than feed deprivation in goats, although shrinkage may increase with increasing feed-withdrawal times. 相似文献
34.
Elizabeth Yaa Parkes Martin Fregene Alfred Dixon Bright Boakye-Peprah Maryke Tine Labuschagne 《Euphytica》2013,194(1):13-24
Breeding for resistant genotypes is the best strategy to offset the destructive effects of cassava mosaic disease (CMD) and cassava bacterial blight (CBB). Two sets of diallel parents were selected for the forest and the savannah ecological zones in Ghana based on good levels of resistance to CMD and CBB. Both sets were crossed in a half-diallel design. The first set of seven progenitors and their 21 F1 progenies were planted in a randomised complete block design (RCBD) with three replications in two different locations for two seasons in the forest ecology. The second set of five progenitors and their 10 F1 progenies were planted in a RCBD with three replications in two locations in the coastal savannah ecological zone of Ghana. Both experiments were evaluated for CMD and CBB resistance, fresh root yield, dry root yield, root number, harvest index, dry matter content, plant height at maturity and height at first branching, levels of branching and plant vigour. Results of the combined analysis of variance revealed that the environment effect was significant for all the traits. General combining ability and specific combining ability effects were significant for most of the traits. Narrow sense heritability was significant for plant vigour, root number, CMD and CBB in both the zones. CMD and root number also had a predictability ratio of close to one, indicating the importance of additive gene effects. 相似文献
35.
Amoah Isaac Cairncross Carolyn Osei Emmanuel Ofori Yeboah Jacqueline Afua Cobbinah Jesse Charles Rush Elaine 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(3):329-339
Plant Foods for Human Nutrition - Bread is a commonly consumed staple and could be a viable medium to deliver plant-based ingredients that demonstrate health effects. This review brings together... 相似文献
36.
Effect of cutting date and frequency on yield and quality of kudzu in the southern United States 总被引：1，自引：0，他引：1
T.H. Terrill S. Gelaye S. Mahotiere E. A. Amoah S. Miller W. R. Windham† 《Grass and Forage Science》2003,58(2):178-183
Kudzu [Pueraria lobata (Willd.) Ohwi.], a vigorous, perennial warm‐season legume, grows widely throughout the south‐eastern United States, predominantly as a volunteer species. It is tolerant of drought and acidic, infertile soils and may have potential as a low‐input forage for livestock. A field experiment was undertaken to determine the effects of cutting date and frequency on yield and nutritive value of kudzu (20‐year‐old stand with no fertilizer or lime inputs) in central Georgia. The cutting treatments included an uncut control, and plots cut once (September), twice (July and September), and three times (June, July, and September) during the 1994 growing season. Dry matter (DM) production and forage quality were determined for total herbage, leaf and stem tissues from quadrat samples taken on all plots in June, July, September, and November (after a killing frost) in 1994, and in June, 1995. Total herbage and leaf DM production was highest for the three‐harvest system and lowest in the no‐cut control plots in 1994, but these results were reversed in the harvest made in 1995. Total herbage production and crude protein concentrations were similar in kudzu cut in the initial summer harvest (either June, July, or September) during the first year. Whole plant and stem in vitro dry matter digestibility (IVDMD) in these samples declined throughout the growing season, while leaf IVDMD was unchanged until the first frost. Kudzu has the potential to be a low‐input forage for livestock, particularly as supplemental drought feed, or as a protein bank for summer or autumn grazing. 相似文献
37.
Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on
yield. This report analyses tuber number, tuber weight, and tuber length of BC2 and BC3 substitution into ssp.andigena cytoplasm and BC2 and BC2 substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were
significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between
reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than
cytoplasmic factors.
Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station. 相似文献
38.
Summary Genes ofSolanum tuberosum L. ssp.tuberosum were introduced into cytoplasm ofS. tuberosum ssp.andigena (Juz. & Buk.) Hawkes andS. phureja Juz. & Buk. to reduce cytoplasmic sterilities. Alleles that influenced berry set and seed content produced differences between
reciprocal progenies. Their expressions were interpreted in terms of genes of the maternal and/or paternal parents. When the
ssp.andigena genotype was introduced from the maternal parent if favoured high berry set and low seed number. Maternal ssp.tuberosum favoured lower berry set and higher seed number. The source ofS. phureja cytoplasm, aS. phureja×S. chacoense F1, used as maternal parent favoured lower berry and seed set. During successive backcrosses progeny expressions approached
those of the recurrent ssp.tuberosum pollen parents. A low level of pollen sterility occurred in BC2 plants, unrelated to direction of cross or cytoplasmic factors. By BC4, seed set and fertility were as good as ssp.tuberosum, and recurrent backcrossing could be terminated without loss of seed production or fertility.
Pennsylvania Agricultural Experiment Station Journal Series No. 7493. 相似文献