Australian Journal of Crop Science最新文献

{"title":"Production and availability of good quality seed potatoes in the East African region: A review","authors":"J. Muthoni, H. Shimelis, J. Mashilo","doi":"10.21475/ajcs.22.16.07.p3566","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.07.p3566","url":null,"abstract":"Demand for potatoes has grown rapidly in eastern Africa due to rapid population growth, urbanisation and life style changes. This has made potato an important commodity crop in the region contributing to food security and enhanced livelihoods. However, potato productivity in the region is low; ranging from 6 to10 t/ha against potential yields of over 30 t/ha. One of the major causes of low yields is the chronic shortage of good quality seed potatoes for planting, which also limits adoption of new and improved varieties. Therefore, the objective of this paper is to highlight the opportunities and progresses in the production and availability of good quality seed potatoes in the East African region to bolster the productivity and commercial value of the crop. The first section of the paper discusses the status of good quality seed potatoes production and availability in the East African region. The second section looks at the farmer-based seed potato production technologies while the third section focuses on the efforts of both the private and public sector in production of good quality seed potatoes. Availability of good quality seed potatoes constitutes < 1% of the requirement in eastern Africa. These seeds are mainly produced by public research institutions as well as some private players. Consequently, most farmers opt to plant seed potatoes from informal sources. However, seeds from informal sources are mostly of poor quality and often accelerate the spread of tuber-borne diseases, especially viruses and bacterial wilt. To improve seeds from informal system, some technologies have been identified and promoted to enhance farmer-based seed production and distribution. These include seed plot technology (SPT), positive selection techniques (PST) and Quality Declared Seed (QDS) systems. In addition, there has been adoption and promotion of rapid multiplication techniques (RMT) such as stem/shoot cuttings, aeroponics, sandponics, and hydroponics among others. Other measures that have been taken include importing seeds of new potato varieties. The imports increase the quantity of seeds and the number of potato varieties available to farmers. Despite these efforts, the quantity of good quality seeds available is still far below the requirements. There is need for the governments, private sector players as well as farmers to enhance their efforts and save the situation. Governments need to invest seriously in local breeding activities and multiplication of early generation seeds. These and other measures may increase availability of good quality and affordable seed potatoes in East African region.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75990126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil physical attributes in an integrated crop-livestock system with pasture managed under different sward canopy heights and different timings of nitrogen application","authors":"Wilson Henrique Tatto, A. B. Soares, T. S. Assmann, J. R. R. Campos, R. L. Missio, Pablo Antônio Beltran Barriga","doi":"10.21475/ajcs.22.16.07.p3226","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.07.p3226","url":null,"abstract":"This study aimed to evaluate the physical attributes of soil in an integrated crop-livestock system with winter pastures managed under different N fertilization timings and canopy heights after winter and the soybean crop. The experimental design used was randomized blocks with the treatments in a 2 × 2 factorial arrangement (two canopy heights and two N application timings), with three area replications. The canopy heights were 11 and 24 cm kept by continuous stocking grazing method since May to November (175 days). Fertilization timings as N-pasture fertilization and N-corn fertilization (phase before the winter pasture). Treatments characterized as N fertilization inversion were applied with fertilization timings as N-pasture fertilization and N-corn fertilization (phase before the winter pasture). Soil density, total porosity, and moisture content were evaluated after winter pasture (black oat + annual ryegrass) and after the subsequent summer soybean crop. The sampling spots were georeferenced and analyzed using geostatistics, considering the position in the slope of landscape. Soil physical attributes were not influenced by canopy height nor N fertilization timing (P>0.05). Soil density was reduced by 13.3% (from 1.11 to 0.98 g cm-3), whereas total porosity (from 0.58 to 0.62%) and moisture content (from 32.73 to 35.73%) increased by 6.9% and 9.2% after the soybean crop in relation to the values obtained in the winter pasture. The higher elevation areas had higher moisture content, total porosity, and lower density than the lower elevation areas, regardless of the time of evaluation. Well-drained soils were more resistant to compaction by animal trampling than moderately drained soils. In well-managed integrated crop-livestock systems in humid subtropical climate regions, the surface compaction of clayey soils in winter pastures is light, non-limiting, and disappears after the subsequent summer crop.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86229131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The density and sowing time of buckwheat in organic and conventional growing system","authors":"J. A. D. Rosa, J. P. D. Silva, R. Vicenzi, Ana Paula Cecatto, Angélica Reolon Costa, C. L. Peter, N. Basso, I. Carvalho, F. Lautenchleger, J. Sgarbossa, D. D. R. Fraga, Willyan J. A. Bandeira","doi":"10.21475/ajcs.22.16.07.p3604","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.07.p3604","url":null,"abstract":"The adjustment of buckwheat density and sowing time in an organic growing system guarantees satisfactory productivity with better environmental quality. The objective of the study is to adjust the sowing density and the best growing season of buckwheat, comparing the organic and conventional growing system. In the study, two experiments were conducted in 2017 and 2018. Experiment one, in a randomized block design with eight replications in a 4 x 2 factorial, for sowing density (40, 80, 120 and 160 kg ha-1) and growing location (Augusto Pestana and Três de Maio, RS, Brazil), respectively. Experiment two, in a randomized block design in a 2 x 2 factorial with eight replications, for sowing time (September and December) and growing system (conventional and organic), respectively, carried out in Augusto Pestana, RS. Grain yield and other characters of agronomic interest of the species were evaluated, with means analysis and regression adjustment. The sowing density around 110 kg ha-1 brings benefits in the buckwheat growing in reaching maximum grain yield in conventional and organic systems. Sowing in September and December is possible regardless of the production system. However, grain yield is maximized under the milder temperature conditions of September. The grain yield in an organic system, although statistically inferior to the conventional one, proves to be advantageous due to the reduced variation in yield due to add value of the product without the use of pesticides and fertilizers","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83231663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Special Issue 2021","authors":"","doi":"10.21475/ajcs.21.15.09.sp","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.09.sp","url":null,"abstract":"","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84631063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"July 2021","authors":"","doi":"10.21475/ajcs.21.15.07","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.07","url":null,"abstract":"","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75052349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphophysiology of Jatropha curcas L. plants under different water regimes","authors":"T. Campos, W. S. Sousa, Alan Abadio da Silva, Valdivino Domingos de Oliveira Júnior, Walter Pires Júnior, T. F. Jesus, L. P. Borges, F. S. Matos","doi":"10.21475/AJCS.21.15.03.P2705","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.03.P2705","url":null,"abstract":"The effect of different water regimes on Jatropha curcas seedling growth was investigated. The study was carried out in a greenhouse covered with transparent plastic. Seeds were sown in five-liter recipients containing substrate consisting of 3:1:0.5 soil, sand and manure, respectively. A completely randomized plot design was used with seven treatments and five replications. The plants were irrigated with 100% substrate retention capacity until 30 days of age when they were submitted to water volumes of 25%, 50%, 75%, 100%, 125%, 150% and 175% substrate retention capacity for 30 days. The short duration of the research explains the slight decreases in the RMR and TRA but they were sufficient to support the assertion that excess water may have inhibited aquaporin activity and partially reduced soil solution absorption and TRA. Thus, both water deficit and excess water inhibited the growth of J. curcas plants, however, the water deficit inhibited more strongly the development of the species at the initial stages of the restriction, while excess water only caused damage after a longer period of exposure. The assessments were made when the plants were 60 days old. The J. curcas plants showed an isohydric mechanism of stomatal control and maintained turgidity under water shortage, and, under excess water, the alterations in the root system and relative water content preceded reduction in stomatal conductance. The initial growth of J. curcas plants was shown to be sensitive to water shortage and but not very vulnerable to water excess.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74428712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late summer organic tomato production with heat tolerant tomato cultivars","authors":"Samantha Hilborn, Michael Petersen, R. Pratt","doi":"10.21475/AJCS.21.15.03.P2892","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.03.P2892","url":null,"abstract":"Field production of organic fresh-market tomatoes in the U.S. Desert Southwest is desired by local producers and consumers. Tomato yield and fruit quality can be seriously impacted by heat stress (HS) and beet curly top virus (BCTV) infection of the main-season crop. We examined delayed planting of HS tolerant cultivars as a strategy for avoiding and mitigating these abiotic and biotic stressors. In 2016, seven putative HS tolerant cultivars, and one considered to be heat susceptible, were transplanted to the field in mid-summer to avoid peak populations of beet leafhopper (Circulifer tenellus), the vector of BCTV. In 2017, seven HS tolerant cultivars, one heatsusceptible, and two hot-set hybrid cultivars were transplanted in mid-summer. Fruit set was above 75% for most entries, including the heat-susceptible checks. Open-pollinated (OP) and hybrid cultivars exhibited a range of yields from 21.3 to 148.6 Mg/ha and fruit quality ratings from poor to excellent. The OP check ‘Super Sioux’ displayed consistently good yield and quality across years. The correlation between fruit set and yield was low (R 2 = 0.29) and significant only at the 0.10 level (P<0.09). The incidence of curly top (incited by BCTV infection) was less than 10% in both years, indicating mid-summer planting aided disease avoidance. ‘Flamenco’, the earliest variety, and two later maturing varieties ‘Florida 91’ and ‘Skyway 687’, are recommended for further evaluation. Mid-summer planting of small and medium-fruited tomato cultivars appears to be a viable option for organic fresh-market tomato production for the fall market in the Southwest USA.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72768407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cultivation of ruziziensis grass (Urochloa ruziziensis) using swine liquid manure fertilization","authors":"Marinho Rocho da Silva, J. Abreu, O. L. S. Weber, L. V. Barros, Edna M. B. Silva, A. Damasceno, W. M. Oliveira","doi":"10.21475/AJCS.21.15.03.P2751","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.03.P2751","url":null,"abstract":"The objective of this study was to evaluate the use of liquid swine manure (LSM) as fertilization in the implantation of Urochloa ruziziensis. The experimental design was randomized blocks with five treatments and four replications, with the treatments being four doses of LSM (0; 100; 200 and 300 m 3 ha -1 ) and one dose of mineral fertilization. Seven cuts were carried out uniformly, after which plant height (PH), total dry mass yield (TDMY), crude protein content (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF), macromineral extraction (N, P, K, Ca, Mg and S) and microminerals (Fe, Zn, Mn and Cu) of plants were evaluated every 30 days. Mineral fertilization provided higher PH, CP content and extraction of N and S, but lower NDF content. For ADF variable, there was no difference between treatments. The results of dry mass yield (DMY) and extractions of P, K, Ca and Mn showed that the effect of 300 m 3 ha -1 LSM was statistically equal to mineral fertilization. For extractions of Mg, Fe, Zn and Cu doses of 200 and 300 m 3 ha -1 did not differ statistically from mineral fertilization. Among the doses of LSM, there was increasing linear effect, with increases in the variables DMY (30.89%), PH (14.94%), CP (17%), N (53.01%), P (40.79%), K (27.84%), Ca (35.17%), Mg (29.6%), S (47.13%), Fe (31.2%), Zn (31.6%) and Mn (23.04%). For Cu extraction, there was a quadratic effect with the highest extraction in the dose of 26.36 m 3 , obtaining an increase of 19.94% in relation to treatment without application. It is important to study different LSM dosages to avoid risk of heavy metal toxicity. The LSM is an alternative in place of mineral fertilization for Urochloa ruziziensis grass.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81530073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of potassium fertilizers associated with cold storage on peach (Prunus persica L.) quality","authors":"Caroline Farias Barreto, L. V. Ferreira, R. Navroski, Jorge Atílio Benati, R. Cantillano, M. Vizzotto, G. Nava, L. Antunes","doi":"10.21475/AJCS.21.15.03.P2438","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.03.P2438","url":null,"abstract":"Potassium (K) fertilization may affect peach quality and preservation. This study aimed at evaluating the effect of doses of K on physico-chemical and functional characteristics of \"Sensacao\" peaches in the postharvest period. Mass loss, pulp color, total solublesolids, titratable acidity, pH, pulp and skin firmness, total concentrations of phenolic compounds and carotenoids and antioxidant activity were evaluated in fruits. The experiment was a randomized block design in a 5x3 factorial scheme, five doses of fertilizers (0, 40, 80, 120 and 160 Kg ha-1K2O) and three storage periods (harvest day, 10 days and 20 days in cold storage at 1±1oC, followed by a day of simulated commercialization at 20±1oC). Mass loss, pulp firmness, phenolic compounds, antioxidant activity and carotenoids decreased when fruit underwent cold storage, independent of the dosage of K fertilization. Doses of40 and160 kg ha-1K2O applied to the soil lead to a larger number of phenolic compoundsand higher antioxidant activity in fruits at harvest time. After cold storage, fertilization with160 kg ha-1K2O exhibited the highest antioxidant activity and the lowest mass loss in fruits. Increase in doses of K strengthened the color of peach pulp.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88030411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of initial spacing on the diameter of hybrid Eucalyptus grandis x Eucalyptus urophylla in a systematic design","authors":"Mirella Basileu de Oliveira Lima, M. E. Nappo, K. L. Soares, R. Castro, E. P. Miguel, T. S. Soares, R. Gaspar, P. Aquino, Renan Augusto Miranda Matias","doi":"10.21475/AJCS.21.15.03.P2935","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.03.P2935","url":null,"abstract":"We evaluated the effect of initial spacing on the distribution of Eucalyptus grandis x Eucalyptus urophylla tree diameters in a Nelder wheel design. The study area was in west-central Brazil. A Nelder wheel design with three repetitions was used. This design provides 432 planting spots per plot/repetition. Planting density varied from 0.50 m2 to 41.25 m2. The diameter at breast height was measured for all plants every four months until 36 months of age, totaling eight measurements. The description of the diameter distribution was developed by fitting probability density functions for each spacing and age. The quality of fit was evaluated using the root mean square error percentage, Pearson’s correlation coefficient, and the Kolmogorov-Smirnov test (α < 0.05). The spacings up to 1.17 m2 must be harvested in less than two years, since it is noted that in the third year the increment in diameter is static and the mortality rate increases. The spacing highly affects the diameter structure of the population, impelling the forester to consider different uses for the wood. For wood requiring larger diameters, spacing above 8.69 m2 per tree is recommended.","PeriodicalId":8581,"journal":{"name":"Australian Journal of Crop Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78054833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}