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Nahla Bassil Kim E. Hummer Joseph D. Postman Gennaro Fazio Angela Baldo Isabel Armas Roger Williams 《Genetic Resources and Crop Evolution》2009,56(3):339-352
Heritage apple (Malus domestica Borkh. hybrids) and pear (Pyrus communis L. hybrid) trees grow in villages throughout Terceira Island, Azores, Portugal. Some of these pears have different names but similar morphology. The objective of this study was to determine synonymy, homology, and phylogeny of apples and pears from Terceira and to examine potential relationships of the island pears with standard apples and pears of Portuguese or American descent. Nine apple microsatellite markers were used to determine genetic relationships. Distance- and parsimony-based cluster analysis grouped these genotypes into separate apple and pear clades. The Terceira apples were divided into two clades: the maçā and the reineta-reinette. Among the 17 heritage apple genotypes, seven unique accessions were identified and four groups of synonyms, or possibly clones, were detected including: ‘Reineta Agosto’ and ‘Reineta Verde’ from Altares; ‘Reineta Castanha’ and ‘Reineta Verde Miuda’; ‘Maçā Pêra,’ ‘Maçā Calhau’, ‘Pêro Branco’ from Salga and from Terra-Chā and ‘Maçā Marmelo’; and the five genotypes ‘Maçā Sao Joao’, ‘Malápio Rosa’, ‘Maçā Gaspar’, ‘Maçā Branca’ and ‘Maçā Pato’. In addition, two homonyms were detected. ‘Pêro Vermelho’ from Terra Chā was a separate genotype from a tree from Doze Ribeiras of the same name, but Pêro Branco from Terra Chā appears to be a clone that can be distinguished by an additional allele at CH1F07a from a tree with that name from Salga. One pair of apple clones, ‘Reineta Agosto’ and ‘Reineta Verde’ from Altares appear to be derived from an unreduced gamete of ‘Golden Delicious.’ Another apple genotype ‘Maçā Acida’ could be a sibling of the ‘Maçā Pêra’ clonal group. Other tested standard apples from the US genebank were unrelated to Terceira genotypes. Of the seven heritage pears, five unique genotypes and one pair of synonyms were detected. ‘Pêra Papo Pintassilgo’ from Raminho and ‘Pêra Vermelha’ from the nursery of Serviço de Desenvolvimento Agario da Terceira (SDAT) were synonyms. ‘Passans du Portugal’ was related to ‘Pêra Cabaca’ but other standard pears from the US genebank were unrelated to Terceira genotypes. Future studies will include additional apple and pear cultivars from other Islands of the Azores and continental Portugal, and wild Asian species to further explore genetic relationships. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(13-14):2313-2340
Abstract Agrostis capillaris ’Parys’, Beta vulgaris cicla ’Fordhook Giant’ (Swiss chard), Brassica oleracea ’Lion Heart’ (cabbage), Cineraria ’Miranda White’, Festiica rubra litoralis ‘Merlin’, Matthiola incana ‘Austral Apricot’ (stock), Phaseolus vulgaris ’Hawksbury Wonder’ (bean), and Polycarpaea spirosrylis (Copper Weed) were grown in pine bark‐based soilless media of pH 4.5, 5.5, and 6.5 amended with copper or zinc sulfate or composts containing high concentrations of either copper (Cu) or zinc (Zn). Growth responses ranged from none, through iron (Fe) deficiency, to symptoms of severe Cu or Zn toxicity. Correlations between growth and shoot Cu or Zn concentration on the one hand and total metal content of the medium and several measures of extractable metal content on the other were obtained. Medium pH had to be included in regressions to obtain high correlation coefficients. Total metal content and DTPA‐ and NH4OAc‐extractable metals were about equally well correlated with growth response in these experiments, but when the results were combined with those from an experiment in which sewage sludge was the source of Cu and Zn, DTPA‐and NH4OAc‐extractable metals gave better correlations than did total content. 相似文献
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Christos Chatzissavvidis Ioannis Therios Chrysovalantou Antonopoulou Kortessa Dimassi 《Journal of plant nutrition》2013,36(4):638-658
Own rooted olive plants (Olea europaea L.) of the cvs. ‘Megaritiki’ (M), ‘Chondrolia Chalkidikis’ (C), ‘Amfissis’ (A), ‘Kalamon’, ‘Koroneiki’, ‘Agiou Orous’, and wild olives, as well as the scion x rootstock combinations CxC, MxC, MxM, AxM, CxM, AxA, and CxA were irrigated with a nutrient solution containing 10 mg boron (B)/L for two months. In all the own rooted plants and in the rootstock—scion combinations of the same cultivar stem growth rate was decreased due to high B. The lowest B concentration in leaves and roots was found in ‘Kalamon’ and wild olives, respectively. ‘Megaritiki’ had higher leaf B concentration when grafted on ‘Megaritiki’ or ‘Chondrolia Chalkidikis’ compared to own rooted plants. The same cultivar as own rooted plant had higher root B concentration than as rootstock of the other tested cultivars. 相似文献
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【目的】探究不同苹果品种对低磷、低氮及低磷低氮胁迫的生理响应,为养分高效利用苹果品种的选育提供理论基础。【方法】采用沙培盆栽试验方法,供试材料为三年生‘嘎拉’/M9T337、‘富士’/M9T337和‘蜜脆’/M9T337矮化自根砧苹果(M9T337为矮化砧木)。以改良1/2Hoagland营养液为基础,设置正常、低氮两个氮水平(NO3~–15、1.5 mmol/L)和正常、低磷两个磷水平(H2PO4~–1.0、0.1 mmol/L),共配置适氮适磷、适氮低磷、低氮适磷和低氮低磷4个处理。测定了苹果树体生长、叶片光合作用和叶绿素荧光参数,分析了苹果叶片氮、磷代谢相关酶活性,树体氮、磷累积量。【结果】与适氮适磷相比,适氮低磷和低氮适磷条件下,‘嘎拉’和‘蜜脆’的植株总干物质量均显著降低,‘富士’的植株总干物质量有显著增加;适氮低磷条件下的‘嘎拉’、‘富士’和‘蜜脆’叶绿素b含量均显著降低,Fo呈升高趋势,但‘嘎拉’和‘富士’的Fv/Fm显著升高且Pn... 相似文献
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Poul Hansen Hans Chr. Jacobsen J. Vittrup Christensen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):181-184
Abstract The apple cultivars ‘Discovery’, ‘Jonagold’ and ‘Mutsu’ were planted in 1980 at row distances of 3 and 4.5 m. Tree heights of 1.5, 2 and 2.5 m were established at 3 m row distance, and 2.25, 2.75 and 3.25 m at 4.5 m row distance. The tree heights were effective from 1985–86; yield and fruit development were followed during 1982–90. Yield per tree, tree size and fruitfulness were larger at the wider row distance, especially for ‘Mutsu’. Thus, in ‘Mutsu’, yield per hectare at 4.5 m equalled that at 3 m, contrary to ‘Discovery’ and ‘Jonagold’, where yield per hectare was higher at 3 m. Also, dry matter contents and colour development (‘Jonagold’) were improved by 4.5 m row distance in several cases. Reduced tree heights decreased yields and colour development (‘Jonagold’), but with minor reductions at tree heights of 2.0–2.5 m during the first 7–8 years. A tree height of 1.5 m, at 3 m row distance, responded negatively, especially for ‘Discovery’ and ‘Jonagold’. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(21-22):3263-3280
The pineapple cultivars ‘Moris’ (Queen cultivar), ‘N‐36’ (‘Sarawak’ × ‘Gandul’ hybrid), ‘Gandul’ (Singapore Spanish cultivars), and ‘Josapine’ (‘Singapore Spanish’ × ‘Smooth Cayenne’ hybrid) are mostly grown on peat soils in Malaysia, whereas ‘Sarawak’ (‘Smooth Cayenne’ cultivar) is more commonly grown on mineral soils. To obtain good yields of fruit of high quality, it is important to understand the differences in nutrient requirements for these cultivars in the different soils in which they are grown. Therefore, the objectives of the study were to determine the biomass and nutrient partitioning of the different pineapple cultivars and to determine the plant variables affecting fruit yield and quality. Plants of each of the pineapple cultivars were randomly sampled from different locations of the major pineapple‐growing areas in Malaysia. Only plants having A‐grade fruit of marketable quality at harvest were selected. The cultivars and respective field sites were as follows: ‘Sarawak,’ Bukit Tandak farm, Kelantan (5° 55.274′ N, 102° 00.608′ E); ‘Moris,’ ‘N‐36,’ and ‘Gandul,’ Peninsula Pineapple Plantations, Simpang Renggam, Johor (1° 49.909′ N, 103° 14.053′ E); and ‘Josapine,’ Goh Swee Eng Pineapple Farm, Simpang Renggam, Johor (1° 48.441′ N, 103° 11.935′ E). Plants were partitioned into roots, stem, leaves, peduncle, fruit, and crown, and fresh and dry weights were recorded. Total biomasses for the different cultivars were 733.46 ± 22.83 g for ‘Gandul,’ 842.34 ± 43.26 g for ‘N‐36,’ 927.38 ± 53.10 g for ‘Moris,’ 434.77 ± 16.82 g for ‘Josapine,’ and 2446.94 ± 156.00 g for ‘Sarawak.’ Leaves accounted for the greatest proportion of dry matter (48.5%), followed by fruit (22.9%) and stem (21.6%), and a smaller proportion (1.2–2.5%) was roots, peduncle, and crown. The proportions of the dry‐matter accumulation in leaves and stem for the cultivars were 53.5 ± 0.7 and 16.7 ± 0.9% for ‘Gandul’; 45.1 ± 0.5 and 17.7 ± 0.7% for ‘N‐36’; 51.9 ± 1.6 and 16.8 ± 0.6% for ‘Moris’; 56.5 ± 1.0 and 12.0 ± 0.9% for ‘Josapine’; and 54.2 ± 5.1 and 27.7 ± 4.4% for ‘Sarawak.’ The proportion of the macro‐ and micronutrients in pineapple parts differed widely between cultivars. Potassium (K) showed the greatest proportion (7.96 ± 0.6 to 29.73 ± 1.17%) in leaves and (4.46 ± 0.70 to 9.35 ± 0.28%) in fruit followed by nitrogen (N) and phosphorus (P) with lower proportions. Most pineapple cultivars grown showed variation in nutrient‐use efficiency (NUE) with respect to the elements measured with values of <1.0 g dry matter g?1 nutrient. The NUE values of >1.0 g dry matter g?1 nutrient were observed for magnesium (Mg) in ‘Gandul’ and ‘N‐36’ and for calcium (Ca) and copper (Cu) in ‘N‐36.’ Total nutrient accumulation in the plant components differed approximately according to their cultivar origins (‘Smooth Cayenne,’ ‘Queen,’ ‘Singapore Spanish’). It is interesting that the results for the ‘Singapore Spanish’ × ‘Smooth Cayenne’ hybrid Josapine were more similar to the ‘Singapore Spanish’ cultivars than being between the parents. Partitioning of biomass and nutrients in pineapple provides a means to categorize them and makes it possible to use a cultivar‐based fertilization program. 相似文献
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Abstract The distribution patterns of dry matter and P in field‐grown tomato ‘Campbell‐37’, ‘Knox’, and ‘Tipton’, (Lvcopersicon esculentum mill), were determined from 25 days after emergence to harvest. Dry weight accumulation was about the same for the 3 cultivars up to 55 days after plant emergence. From 55 to 75 days, ‘Knox’ accumulated more total plant dry weight than either ‘Tipton’ or ‘Campbell‐37’, largely due to an accelerated fruit accumulation rate during this period. In the 75 to 105 day interval, dry weight accumulation by ‘Knox’ was less than ‘Campbell‐37’ or ‘Tipton’. Fruit accumulation, as indicated by fruit number increase, was during the 45 to 75 day period for ‘Knox’, the 55 to 75 day period for ‘Tipton’, and the 55 to 85 day period for ‘Campbell‐37’. ‘Knox’ and ‘Tipton’ had a faster fruit ripening rate than ‘Campbell‐37’. The total ripe fruit yields, for single and multiple harvests, were 36.7% and 28.6% respectively, higher in ‘Campbell‐37’ than in ‘Knox’. Phosphorus concentration of stem, leaf, and cluster tissues decreased over the season for the 3 cultivars. Phosphorus concentrations of leaves decreased from 0.49% to 0.16% as plant development progressed from seedling stage to ripe fruit harvest. Phosphorus in the vegetative portion of the tomato plant at final harvest represented only about 10% of the total P accumulated. The plant efficiency with respect to P accumulation decreased from an early stage of plant development as the relative growth rate of the plant declined. 相似文献
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Hamide Gübbük Mustafa Pekmezci Mustafa Erkan 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):249-253
The objective of this study was to evaluate the production potential of banana cultivars, ‘Grand Nain’, ‘Petit Nain’, ‘Poyo’, ‘Williams’ and ‘Basrai’, as alternatives to the ‘Dwarf Cavendish’ for open-field and greenhouse cultivation in subtropical conditions. Stem circumference, stem height, total leaf number, bunch stalk circumference, days from shooting to harvest, number of hands per bunch, number of fingers per bunch, finger circumference, finger length and bunch weight were measured in open-field and greenhouse cultivation. Cultivars ‘Williams’ and ‘Grand Nain’ were superior to ‘Dwarf Cavendish’ in greenhouse cultivation, while these two cultivars and ‘Petit Nain’ and ‘Basrai’ were superior to ‘Dwarf Cavendish’ in open-field cultivation. ‘Poyo’ was not suitable for greenhouse cultivation because of its excessive height and for open-field cultivation due to its sensitivity to wind damage. Greenhouse cultivation of bananas was superior to open-field cultivation for all cultivars with increases in yield of 19 to 28% according to the cultivar. 相似文献
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磺胺类兽药对土壤生化功能及氮素的影响 总被引:3,自引:0,他引:3
研究了磺胺类药物对土壤呼吸作用、硝化作用、氨化作用、铵态氮、硝态氮、亚硝态氮及全氮的影响。结果表明,相对较低浓度药物残留(10 mg/kg土)对土壤呼吸作用的影响呈现"激活-抑制"循环的规律,而相对较高浓度药物残留(50 mg/kg土)对土壤呼吸作用的影响则呈现"抑制-激活-抑制"的规律,因此,磺胺类药物残留会抑制土壤呼吸作用。相对较低浓度药物残留(10 mg/kg土)对土壤硝化作用、氨化作用呈现"激活-恢复"的规律,而相对较高浓度药物残留(50 mg/kg土)对土壤硝化作用、氨化作用则一直呈现"激活"的状态,因此,磺胺类药物残留会刺激土壤的硝化作用与氨化作用。土壤氮素是生物圈内氮循环的重要指标,磺胺类药物残留对土壤氮素有一定的抑制作用,若长期保持着较高残留水平,则会破坏土壤的氮循环。 相似文献
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Sap mixtures of the xylem, phloem, and vacuoles from low and high Cd accumulator varieties of Brassica parachinensis L. H. Bailey were analyzed under Cd stress to understand the biochemical mechanisms of Cd accumulation in plants. Low Cd accumulator (‘Teqing-60') and high Cd accumulator (‘Chixin-2') plants were grown in Cd-treated soil in pots in a greenhouse. Percentage of cell wall-bound Cd was estimated, pH level and the concentrations of amino acids, organic acids, anions, and cations in both stem and root saps were determined for the calculation of Cd speciations using the computer program GEOCHEM. The results showed that ‘Teqing-60' had a significantly higher (P ≤ 0.05) percentage of Cd bound to cell walls in roots and a significantly higher (P ≤ 0.05) pH in the root sap. ‘Teqing-60' also contained a higher concentration of total amino acids in both roots and stems compared with the high Cd accumulator variety ‘Chixin- 2'. However, between the two accumulators, for stems and for roots, there were no significant differences in non-amino organic acids. GEOCHEM calculations showed that Cd in the root sap of ‘Teqing-60' mainly combined with amino acids, especially alanine. Compared with ‘Chixin-2', in the root sap of ‘Teqing-60', much lower levels of Cd as free ions or bound to simple ligands were found, indicating that less ‘Teqing-60' is transferred to stems and leaves. Cadmium activity in the shoot sap of ‘Teqing-60' was much lower than that in ‘Chixin-2'; therefore, ‘Teqing-60' exhibited higher Cd resistance. However, direct determination of the Cd complexes from xylem and phloem sap is needed to verify these results. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(17-18):2787-2792
Abstract In nutrition experiments of fruit‐growing areas of central Washington state, ‘Delicious’ and ‘Golden Delicious’ apple (Malus domestica) orchards and ‘d'Anjou’ pear (Pyrus communis L.) orchards with the lowest soil pH values had a high incidence of fruit disorders and the lowest concentration of leaf calcium (Ca). In contrast, orchards with the highest soil pH values had the highest concentration of soil Ca (meq 100 g‐1) and the lowest incidence offrait disorders (bitter pit for apples and alfalfa greening, black end and cork spot for pears). Apple orchards with the highest soil pH values also had ‘Delicious’ and ‘Golden Delicious’ apples containing the highest concentration of Ca, but Ca concentrations in ‘d'Anjou’ pears were not significantly different among the different soil pH groups. 相似文献
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Field experiments were conducted during 1994–1995 in seven apple (Malus spp.) orchards located in the southwest of Finland (the mainland and the Åland Islands). The cultivars were ‘Transparente Blanche’, ‘Samo’, ‘Melba’, ‘Raike’, ‘Red Atlas’, ‘Åkerö’, ‘Aroma’, and ‘Lobo’. Leaf samples from branches bearing fruits (BF) and not‐bearing fruits (BNF) were collected two times during the growing seasons. Fruit samples were picked about one week before commercial maturity. Macronutrient concentrations in fruits and leaves, fruit diameter and juice pH, titratable acidity (TA) and soluble solids concentrations (SSC) were determined. Leaf nitrogen (N), phosphorus (P), and potassium (K) were higher, but calcium (Ca) and magnesium (Mg) were lower in BNF. Branch types (BF and BNF) were closely related in leaf N, P, and Ca, but not in leaf K and Mg at the first sampling time. Fruit N, P, K, and Mg were closely related to each other but not to fruit Ca. Mean fruit N and Ca and leaf P and Mg were low compared with the recommended levels. Relationships between fruit and leaf nutrient concentrations were found only in P and Mg. Fruit diameter increased and juice SSC decreased with increasing leaf N concentration. Fruit P declined with increasing fruit diameter and juice TA increased and SSC/TA decreased with increasing leaf P and Ca concentrations. 相似文献
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An experiment was conducted under greenhouse conditions to test the symbiotic performance and plant nutrient uptake of the twelve nationally registered chickpea cultivars (‘Çak?r’, ‘I??k-05’, ‘Can?tez-87’, ‘Hisar’, ‘Ya?a-05’, ‘Azkan’, ‘Küsmen-99’, ‘Gökçe’, ‘Damla-89’, ‘Diyar-95’, ‘Aziziye-94’, and ‘?zmir-92’) in Turkey. Inoculation with Mesorhizobium ciceri increased the average nodule number by 687%, nodule weight by 257%, plant height by 6%, shoot dry weight by 12%, root dry weight by 21%, chlorophyll content by 4.2%, nitogen (N)% by 7.9%, and total N by 22.7%. Averaged across chickpea cultivars, inoculation also significantly increased sulfur (S) by 14.4%, phosphorus (P) by 1.9%, magnesium (Mg) by 13.8%, potassium (K) by 6.2%, calcium (Ca) by 17.4%, copper (Cu) by 4.5%, iron (Fe) by 16.5%, manganese (Mn) by 10.9% and zinc (Zn) uptake by 9.4%. The macro- and micronutrient uptake of cultivars significantly correlated with their nitrogen content and the magnitude of response to inoculation in relation to nodulation, plant growth, nitrogen fixation, and nutrient uptake significantly varied among cultivars. Based on the amount of fixed N and plant nutrient uptake, ‘Azkan’, ‘Aziziye-94’, ‘Küsmen-99’, ‘Diyar-95’, and ‘Hisar’ were the genotypes with the most positive response to inoculation. Our data showed that nodulation, nitrogen fixation, plant dry matter production, and macro- and micronutrient uptake of the inoculated chickpea can be improved by selecting the best compatible cultivar. 相似文献
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Xiangjun Li Ping An Shinobu Inanaga A. Egrinya Eneji Kenji Tanabe 《Journal of plant nutrition》2013,36(8):1499-1508
An experiment was conducted to determine if salinity stress alters the response and tolerance of soybean to defoliation. Four soybean [Glycine max(L.) Merr.] cultivars (‘Tachiutaka,’ ‘Tousan 69,’ ‘Dare’ and ‘Enrei’) in a growth chamber were exposed to two salinity treatments (0 and 40 mM NaCl) and two defoliation treatments (with and without defoliation). The interactive effects of salinity stress and defoliation on growth rate, leaf expansion, photosynthetic gas exchange, and sodium (Na+) accumulation were determined. The decrease in growth rate resulting from defoliation was more pronounced in plants grown under salinity stress than in those grown without the stress. Without salinity stress, defoliated plants of all four cultivars had leaf-expansion similar rates to those of the undefoliated ones, but the photosynthetic rates of their remaining leaves were higher than those of undefoliated plants. However, with salinity stress, defoliated ‘Tachiutaka’ and ‘Tousa 69’ had lower leaf expansion and photosynthetic rates than undefoliated plants. For cultivars ‘Dare’ and ‘Enrei,’ the defoliated plants had leaf-expansion rates similar to undefoliated ones, but the photosynthetic rate of the remaining leaves did not increase. Except for cultivar ‘Dare,’ defoliated plants grown under salinity stress had higher Na+ accumulation in leaves than undefoliated ones, and this result may be related to slow leaf expansion and photosynthesis. Salinity stress negatively affects soybean response and tolerance of defoliation, and the effects varied according to the salt tolerance of the cultivar. 相似文献
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不同施肥方式对超高产夏玉米叶绿素荧光特性及产量性状的影响 总被引:15,自引:3,他引:12
通过田间试验,研究了不同施肥方式下超高产夏玉米叶片叶绿素荧光参数、SOD活性、细胞膜稳定性及产量性状。结果表明,“种沟施肥+拔节期追氮+大喇叭口期追氮”有利于提高玉米叶片的PSⅡ原初光化学效率(Fv/Fm) 、PSⅡ量子效率(ΦPSII)和光化学猝灭系数(qP), 降低非光化学猝灭系数(NPQ)。“种沟施肥+拔节期追氮+大喇叭口期追氮”和控释肥这两种施肥方式对提高叶片叶绿素含量和SOD活性,降低MDA含量和相对电导率的效果较好。控释肥对提高玉米子粒千粒重的效应较大,“种沟施肥+拔节期追氮+大喇叭口期追氮”显著提高玉米子粒产量。为了获得高产,应采用种沟施肥+拔节期追氮+大喇叭口期追氮的施肥方式,而控释肥则有利于简化施肥作业,提高劳动效率。 相似文献
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A. Sønsteby O. M. Heide R. Rivero F. Måge S. F. Remberg 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):578-587
ABSTRACT Flowering performance and phenology of six new pear cultivars of Nordic origin were examined during a 12 year period. The seasonal timing of shoot growth and flower initiation were monitored in three years. The morphological floral stages of the flower bud formation process were examined for the cultivar ‘Celina’. Seven floral stages were identified and described. The date of full bloom varied between years as a function of the currently accumulated heat sum in early spring. Still, the earliness ranking of the cultivars was consistent across years for both flower initiation and blooming. The cultivars ‘Anna’ and ‘Ingeborg’ consistently initiated floral primordia 2–3 weeks earlier than ‘Celina’, ‘Clara Frijs’, ‘Fritjof’ and ‘Kristina’, and this was accompanied with 4–5 days earlier blooming in the following spring. The early flower initiation cultivars ‘Anna’ and ‘Ingeborg’ also had richer flowering than the late-blooming cultivars. ‘Fritjof’ was identified as a suitable pollinator for ‘Celina’ in the Nordic climate. Comparison of the flowering phenology of pear and apple cultivars showed that while the pears, on average, flowered a week ahead of the apples, they initiated flower primordia almost two weeks later, thus rendering the intervening period approximately three weeks longer in pear than in apple. 相似文献
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《Soil & Tillage Research》1987,9(3):287-300
In a field experiment on cracking clay soil, the effects of soil water content during pre-sowing land preparation and intensity of cultivations during the growing season on soil physical conditions and growth of a furrow-irrigated cotton crop were investigated. Before sowing, cultivations typical of local practice were imposed on soil in a ‘dry’, ‘moist’ and ‘wet’ state, representing three main treatments. During the season, three intensities of inter-row cultivation were superimposed on each of the three main treatments.Soil physical conditions and cotton plant growth were influenced by soil water content during pre-sowing land preparation, but not by subsequent inter-row cultivations. In soil prepared ‘dry’, after the first irrigation significantly more water was extracted by the crop than from either of the other two treatments. The morphology of the post-season soil profile of the land prepared ‘dry’ differed little from the unirrigated and uncultivated pre-season profile, whereas that of the land prepared ‘wet’ had altered considerably, being generally massive to a depth of 0.65 m. Cotton in the land prepared ‘dry’ grew tallest and had most green bolls of any main treatment on most weeks during the season. For most of the season, land prepared ‘dry’ or ‘moist’ had similar above-ground plant dry matter, both having greater amounts than the ‘wet’ treatment. Plant population per metre of row was equal in the ‘dry’ and ‘moist’ treatments, and lower in the ‘wet’. Yield differences were not recorded between treatments as there was high insect damage in the ‘dry’ treatment. 相似文献