Salinity tolerance of bermudagrass (Cynodon spp. L. C. Rich) cultivars and shoot Na,K and Cl contents under a high saline environment

Summary

Increasing need for salt-tolerant turfgrasses continues due to population growth in arid and semi-arid regions where potable water is limited, while soil and existing water sources are salty. Bermudagrass (Cynodon spp. L. C. Rich) is widely used in these areas. Therefore, this experiment was conducted to evaluate the salt-tolerance of ten cultivars of bermudagrass under a high saline soil and water environment. Five salinity levels of irrigation water (3.30, 6.93, 10.2, 14.8 and 17.8 dS m^–1) were prepared and 30 pots were surfaced-irrigated at each salinity level for 1 year. Overall top growth, root growth, K content and K:Na ratio were reduced by 75%, 45%, 77% and 94.5%, respectively; while leaf-firing, shoot Cl and shoot Na concentrations were increased by 4%, 498% and 356%, respectively, when the salinity increased from 3.3 dS m^–1 to 17.8 dS m^–1. Regarding the salt-tolerance of cultivars, ‘Tifway’ was superior in top growth, percentage leaf-firing, Na uptake and K:Na ratio, ‘ISF2’ in root growth, and ‘Tifdwarf’ in Cl uptake. Although ‘Tifway’ showed the greatest reduction in root dry weight, it had the lowest level of leaf-firing and lowest reduction in top growth, which could be due to having the lowest Na uptake. Cultivars exhibited marked differences in their response to salinity; however, no mortality was observed, indicating that all cultivars tolerated the salinity levels used in the experiment.     

Response of eggplants grown in recirculating nutrient solution to salinity imposed prior to the start of harvesting

Summary

The effects of exposing eggplants grown in recirculating nutrient solution to salt stress (6.1 dS m^–1) from planting until the beginning of harvesting, on plant growth, yield and macronutrient status was investigated. The salinity was imposed by adding to a basic nutrient solution either additional nutrients at two cation ratios or NaCl. The results showed that the exposure of plants to salinity prior to the beginning of harvesting reduced both vegetative growth during that time and early fruit yield, but the depression of the latter was more severe. The restriction of the early yield was a result of a reduced mean fruit weight due to a lower fruit water content. The detrimental effects of salinity on the mean fruit weight disappeared 25 d after discontinuing the salinity treatments. As a result, the total yield obtained after five months of harvesting was not influenced by exposing the plants to salinity prior to the beginning of harvesting. The salinity source had no specific effect on plant growth. Moreover, the increase of salinity up to 6.1 dS m^–1 did not cause any specific nutritional imbalance or toxicity to the plants, irrespective of the salts used to achieve it. It is suggested that the electrical conductivity of the nutrient solution may be raised to 6.1 dS m^–1 to control excessive vegetative growth in eggplants grown hydroponically. However, salt treatment should be terminated either at the first harvest, if the total yield is more important than the early yield, or three weeks earlier, if the opposite is true.     

陇南市山地大蒜覆膜优质高产栽培技术

为了推动了山地蔬菜产业发展，利用甘肃省陇南市徽县当地优势“三蒜”品牌，摸索经验，总结出山地大蒜覆膜优质高产栽培技术，优化了品种选择、地块选择、整地施肥、蒜种处理、适期播种、覆膜与破膜、采后管理等技术，有效地提高了陇南市秋播大蒜产量，实现蒜薹增产60%，蒜苗增产50%，蒜头增产45%；提升了大蒜品质，增加了经济效益，大蒜667m²总产值可达8 100元，蒜苗667 m²总产值可达10 000元。     

锌钼与腐殖酸配施对大蒜生理特性及土壤性质的影响

针对影响大蒜生长的土壤障碍因子,研究锌钼与腐殖酸配施对大蒜叶片叶绿素含量、抗氧化能力、大蒜产量及土壤物理、化学、生物学指标的影响。设常规施肥(CK)、常规施肥+锌肥+钼肥(T1)、常规施肥+腐殖酸(T2)、常规施肥+锌肥+钼肥+腐殖酸(T3)4个处理。结果表明,锌钼与腐殖酸配施能够显著提高大蒜叶片叶绿素含量,提高过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性,有利于增强土壤酶(脲酶和磷酸酶)活性,改善土壤理化性质,并能显著增加大蒜株高、茎粗、蒜头直径及产量。T3处理的大蒜产量可达20.13 t·hm~(-2),比当地传统施肥增产14.83%。综上所述,锌钼与腐殖酸配施对于河南蒜区的大蒜产量和土壤质量的改善具有很好的效果。     

Effects of salinity at two ripening stages on the fruit quality of single-truss tomato grown in hydroponics

Summary

Single-truss tomato plants grown hydroponically (wet-sheet culture) were exposed to a salinity (EC) of 5.0 dS m²¹ or 8.0 dS m²¹ at two fruit ripening stages, the immature green stage and the decolouring stage. These salinities were achieved by adding NaCl to the standard solution, which had an EC of 2.4 dS m²¹. Increased salinity at the immature green stage improved fruit quality more than increased salinity at the decolouring stage but decreased fruit yield more. The reduction in fruit yield was due to a decrease in fruit weight but not in fruit number. Salinity increased the concentration of soluble solids, citrate, ascorbic acid, K, chlorophyll a, chlorophyll b, lycopene, and carotene in the fruit, but the absolute amount of these constituents per fruit was decreased or not affected. These results suggest that the improvement in fruit quality induced by the salinity is caused by the reduction of water import into the fruit. The effectiveness of both salinities was significantly bigger when it was applied at the earlier development stage, suggesting that mature fruit would be less sensitive to strength of the EC.     

不同栽培方式对田家紫皮大蒜产量的影响

为提高内江地理标志产品田家紫皮大蒜产量,改善土壤结构,开展了不同播种方式、化肥减量和增施有机肥、大蒜分级消毒处理等多种栽培试验,以研究不同栽培方式对大蒜产量的影响.结果表明:采用浅宽沟撒播和条播的方式有助于增产,其中以浅宽沟撒播并覆盖稻草效果最好,大蒜667 m2增产达到35.4％;在传统穴播方式下,减施化肥和增施有机...     

Influence of potassium humate on biochemical and agronomic attributes of bean plants grown on saline soil

To study the effect of soil application of potassium humate (KH) (0, 70 and 140 Kg ha^?1) on agronomic, biochemical attributes, and yield and its components on bean (Phaseolus vulgaris L.) cultivars ‘Bronco’ grown under two sites having different level of salinity (EC = 3.00 or 5.00 ± 0.20 dS m^?1). Two field trials were conducted at the Agriculture Test Station, Faculty of Agriculture, Fayoum University, in 2014 and 2015. The obtained results indicated that addition of KH increased all of the studied growth parameters, i.e. plant height, number of leaves, leaf area, stem diameter and canopy dry weight. Moreover addition of KH significantly increased membrane permeability measurements. KH significantly increased chemical composition related to salt tolerant either inorganic e.g. N, P, K, and decreased Na and Cl contents of leaves or organic components e.g. chlorophyll a + b, carotenoids, anthocyanin total phenolics, total flavonoids and proline. DPPH radical-scavenging activity and yield and its components were increased. The soil application of KH was found to be highly effective at improving the growth and yield of bean plants by alleviating the inhibitory effects of soil salinity stress.     

Optimization of saline water level for sustainable Barnea olive and oil production in desert conditions

The main aim of the present study is to evaluate the effects of long-term irrigation with water at three different levels of salinity on Barnea olive trees with a view to optimize vegetative growth, productivity and oil quality. The study was carried out on trees growing in the Negev desert of Israel. The intermediate salinity (4.2 dS m⁻¹ EC) inhibited growth significantly only in the first year after planting, while from the second year onward retardation of vegetative growth as compared with the control treatment (1.2 dS m⁻¹ EC) was slight and non-significant. However, the high salinity (7.5 dS m⁻¹ EC) retarded tree growth significantly. Furthermore, the intermediate treatment led to significant increase in tree productivity relative to the other treatments, and also to an increase in olive oil yield. In conformity with the greater number of fruits produced, the olives of the 4.2 dS m⁻¹ EC treatment tended to be smaller.No significant differences were found between saline- and control-water irrigated trees in terms of olive oil basic quality parameters, such as free fatty acids, peroxide value, and fatty acid profile. The saline treatments increased the levels of certain antioxidant components (polyphenols and Vitamin E) in the oil extracted from the olives as compared with the control. The data obtained clearly show that, of the three water salinities tried, the moderate level of 4.2 dS m⁻¹ EC is best suited for production of olives and olive oil under the conditions prevailing in the central Negev, at least during the first 9 years from planting. The sustainability of Barnea cultivation under moderately saline water is discussed.     

轮作对黄瓜连作土壤环境和产量的影响

为了评价栽培制度对连作障碍土壤的修复效果,采用盆栽方式,设置休闲、轮作、间作等处理,以生产中常用的栽培制度即夏季休闲的连作制度为对照,研究各处理对连作8年黄瓜的温室土壤生物修复效果及对后茬黄瓜产量的影响。结果表明,夏季温室休闲期种植青蒜和菠菜及白菜的处理可以显著降低土壤盐分积累,增加土壤微生物数量,抑制镰刀菌的增殖;叶菜－黄瓜－番茄栽培制度较对照收益提高了26.3％,青蒜－黄瓜－黄瓜栽培制度较对照提高了11.6％,黄瓜间作青蒜年收益和对照相近。从本试验的结果来看,填闲和轮作栽培制度可显著改善土壤微生物组成,利于修复连作障碍的土壤。     

Natural bee-honey based biostimulants confer salt tolerance in onion via modulation of the antioxidant defence system

Plant biostimulants are an emerging trend of crop management products which can enhance nutrient uptake, plant growth and productivity under various abiotic stresses. The ability of diluted bee-honey extract (DHE) to enhance the tolerance of onion plants to salinity stress has been investigated. Two-season field experiments were consecutively conducted in 2015/16 and 2016/17 to study the effect of 25–50 g/L DHE foliar application on growth, yield, physio-biochemical attributes, and antioxidative defence of two onion cultivars (i.e. Giza^Red and Giza-20) grown on a saline soil (EC = 8.81 dS m^?1). Results exhibited that DHE significantly increased biomass production, bulb yield and water use efficiency, leaf photosynthetic and pigments contents. Additionally, DHE applicati\on also improves osmoprotectants, membrane stability index (MSI) and relative water content (RWC), and enzymatic and non-enzymatic antioxidants of both onion cultivars in comparison with untreated control plants. In general, both cultivars showed a similar response to the DHE. Results of this study highlighted the potential impact of DHE as a promising plant bio-stimulant for overcoming the harmful effects of soil salinity stress by increasing the activity of plant antioxidative defence systems     

施硒对大蒜产量和含硒量的影响

  以土壤施硒(0. 1 g·m^-2) 研究大蒜对硒的吸收、转化及硒对大蒜产量的影响。结果表明, 4 个大蒜品种吸收硒的能力为: 应县大蒜> 忻州大蒜> 榆次大蒜和太谷大蒜。以土壤施硒(0. 01、0. 1、1、10 g·m^-2) 、叶面施硒(10、100、1 000 mg·kg^-1) 和硒浸种10、100 mg·kg^-1) 3 种方式处理应县大蒜, 结果随着硒处理浓度的提高, 大蒜的产量先升后降,大蒜含硒量随着硒处理浓度的提高而提高, 但无机硒转化成有机硒的比率下降。     

Long-term effect of irrigation with saline water on the development and productivity of jojoba clones

Summary

Three commercial clones of jojoba (Simmondsia chinensis) (64, Q-106 and 879–154) were planted in June 1991 at the Ramat Negev Experimental Station (Israel) and fertigated with water at three salinity levels, 1.2, 3.4 or 6.2 dS m^?1. The effects of salinity over three and a half years on key metabolic activities, on plant growth and development, on flowering characteristics, and on yield were studied. Salinity barely inhibited the rate of net photosynthesis, although it did reduce stomatal conductivity by about 50%. Salinity also affected the water status of the plants by reducing water potential. Growth of the plants was not greatly affected by salinity. It was found that jojoba plants accumulate sodium and chloride ions in their leaves and use a strategy typical of many halophytes to cope with the salinity. The effect of salinity on flower development was also studied, since the vitality of flowers is a key factor in obtaining seeds. Salinity did not affect the timing of the breaking of flower bud dormancy in the 1992-93 season, although it did delay flower bud growth in clones Q-106 and 64. Salinity brought forward the flowering of clone 879–154 by about a fortnight in the 1993-94 season, but did not affect the flowering pattern of the other clones. Fruit set was not inhibited by salinity in the 1994 or 1995 season, and no significant effects were found on yield and wax content in 1994 season, but yield was reduced by salinity in the 1995 season.     

The influence of NaCl salinity on growth,yield and fruit quality of strawberry cvs. ‘Elsanta’ and ‘Korona’

In a 2-year field study, strawberry cvs. ‘Elsanta’ and ‘Korona’ were exposed to three different levels of NaCl salinity supplied as aqueous solutions characterised by electrical conductivities of 0.3 dS/m, 2.6 dS/m, and 5.1 dS/m. Salinity in the rhizosphere reduced plant growth by up to 44% in ‘Korona’ and 90% in ‘Elsanta’. A rather distinct cultivar difference represented the reduction in leaf area per plant of 85% in the second year of experiment in ‘Elsanta’ compared to 29% in ‘Korona’. Strawberry can be regarded as a Na⁺ excluder, because Na⁺ content of both strawberry cultivars remained below 3 mg g⁻¹ dry mass at all salinity levels. Cl⁻ content increased considerably, up to 70 mg g⁻¹ dry mass in ‘Korona’ and 80 mg g⁻¹ dry mass in ‘Elsanta’ plants. ‘Korona’ retained most of its Cl⁻ in roots and crowns, whereas in ‘Elsanta’ the maximum was detected in petioles. ‘Korona’ was able to accumulate up to 33% higher Cl⁻ content in the roots than ‘Elsanta’. Macronutrient deficiency due to NaCl salinity was not observed and in comparison to ‘Elsanta’, higher Cl⁻ content in roots of ‘Korona’ did not coincide with an impairment of macronutrient uptake. Salinity stress reduced fruit yield by up to 27% in ‘Korona’ and 64% in ‘Elsanta’. Fruit quality, characterised as taste, aroma, and texture by a consumer-type panel, decreased by more than 24% in ‘Elsanta’, but in ‘Korona’ differences were insignificant. Total soluble solids (Brix) and the ratio Brix/TA (TA, titratable acid) decreased significantly by about 20% in ‘Korona’ and 35% in ‘Elsanta’. To summarise, the ability of ‘Korona’ to retain Cl⁻ in the root system more effectively than ‘Elsanta’ resulted not only in a 41% lower leaf Cl⁻ content at the highest salinity level and a better growth under NaCl stress, but also in a relatively higher fruit yield and fruit quality.     

大蒜配方施肥对肥料利用率的影响

研究了普通复合肥处理、习惯施肥处理、配方施肥处理下,大蒜对N、P、K肥的利用率以及大蒜产量的变化。研究结果表明,配方施肥可以提高大蒜对N、P、K肥的利用率,且N、P、K收支均基本平衡并有盈余,还可以提高大蒜产量,增加收益,培肥地力。     

Evaluation of Four Commercial Composts on Strawberry Plant Productivity and Soil Characteristics in California

ABSTRACT

Composts can have beneficial effects on strawberry production and these benefits can be dependent on the type of compost used. Four commercial composts were evaluated: cow manure, spent mushroom, yard trimmings, and vermicompost. The nutrient composition, abundance of fungi and bacteria, and microbial activity were determined. Five field trials assessed effects on plant growth, root development, soil microbial activity, nutrient availability, and yield during one growing season. Manure and mushroom compost significantly increased soil electrical conductivity levels to 9.9 ± 1.7 dS/m and 7.3 ± 0.8 dS/m, respectively. Manure, yard trimmings, and mushroom composts shifted soil pH toward optimal levels for up to 7 months. Mushroom compost had the greatest effect on soil nitrate, which was up to 32 mg/kg of soil higher than non-amended soil. Significant effects on yield were more likely to occur where environmental conditions and management practices were less than optimal or compost was not routinely added. Several factors important to plant production were significantly affected by compost: soil salinity, plant establishment, soil nitrate, production curves, soil microbial activity, and soil pH.     

脱毒对民乐紫皮大蒜农艺性状、产量及品质的影响

为了明确脱毒大蒜的田间农艺性状和提质增产效果，采用脱毒民乐紫皮大蒜为试验材料，与未脱毒常规大蒜进行田间比较试验，比较分析了大蒜的生育期、农艺性状与产量和品质。结果表明：与常规大蒜相比较，脱毒大蒜物候期提前3～12 d，生育期缩短了9 d，易形成壮苗；株高、株幅、假茎高、假茎粗、叶长、叶宽、蒜薹长、蒜薹粗、单薹质量等9个农艺数量性状指标增长极显著，增长率分别为19.28%、18.44%、17.77%、18.97%、22.42%、11.52%、33.80%、27.45%、77.90%，叶片数增长显著，增长率为8.80%。蒜薹、鳞茎增产率分别达到136.0%、55.5%，一级鳞茎直径和单鳞茎质量最高达91.21%和90.81%，叶绿素a、叶绿素b、叶绿素a+b分别增加19.05%、18.84%、18.99%，鳞茎总糖、可溶性蛋白、维生素C、大蒜素含量分别增加59.45%、19.86%、23.08%、49.41%，各指标均极显著增加。脱毒有利于提高大蒜生长势，增强农艺性状与单株产量间的相关性，提升商品率和品质，增产效果显著。     

Physiological response of the medicinal plant artichoke (Cynara scolymus L.) to exogenous salicylic acid under field saline conditions

Alleviating salinity stress by modifying the physiology of the medicinal plant globe artichoke (Cynara scolymus L.) was investigated in a field experiment using salicylic acid (SA). The objectives were to determine: (1) the physiological response of artichoke under salinity stress, and (2) whether SA can alleviate the adverse effects of salinity by affecting artichoke physiology. The factorial combination of salty water (control, 8 dS/m, and 14 dS/m) and foliar application of SA (control, 0.1, 1 mM) was tested. A 1500-L tank was used in the field to establish the favorable salinity levels. Salinity increased chlorophyll a and total chlorophyll; however, at the medium level of SA, chlorophyll a decreased. Increasing salinity and SA decreased total phenolic contents. Increased salinity increased plant proline and ionic leakage. Interestingly, SA significantly decreased ionic leakage, compared with the control. SA increased proline production at different levels of salinity. SA at 0.1 mM was the most suitable and effective treatment under salinity stress. It is possible to alleviate the stress of salinity on artichoke growth by modifying plant physiology using the appropriate concentration of SA.     

The effect of split-root salinity stress on tomato leaf expansion,fruit yield and quality

Summary

A crop-scale experiment between March and October 2000 investigated the effects of split-root salinity stress and rooting volume on the expansion of leaves, fruit yield and quality in two standard round fruited cultivars of tomato (Lycopersicon esculentumMill) Solairo and Espero, grown in rockwool. To implement the treatments, a split-root method was utilized whereby different levels of salinity (expressed as EC), adjusted by the addition of NaCl, was administered to two halves of a root system. The split-root high EC (2.8/8.0 dS m^–1) treatment enhanced fruit quality by increasing the concentrations of sugar, acid, total soluble solids and reducing the incidence of visual defects such as uneven ripening and gold-spot. Split-root high EC did however reduce leaf area that corresponded with low K concentration in the leaf tissue. The split-root method utilized doubled the rooting volume compared with the standard single rockwool slab, but this extra rooting capacity had no detectable effect on leaf expansion, yield or fruit quality. Although there was little impact on yield for ten weeks after the imposition of the high EC split-root treatment, mean reductions in weekly yield occurred thereafter and were of the order of 9 and 13% for ‘Solairo’ and ‘Espero’ respectively through to the end of the experiment. The fall in yield was due, in part, to a decrease in fruit size. Whilst water uptake was reduced it was unclear how the effects on leaf growth and fruit yield were mediated in the shoot. Possible processes that coordinate responses to root-zone salinity stress are discussed. The potential use of the split-root system in commercial production is considered.     

磷水平与大蒜产量和品质的关系

盆栽试验结果表明：黄棕壤上施磷水平与大蒜生物学产量呈ｙ＝７．６４＋８．７２ｘ的显著线性相关，但以施磷量（Ｐ２Ｏ５）５００ｍｇ／ｋｇ效果较佳；缺磷土壤施用一定量的磷可促进氮、钾的吸收，提高植物体内大蒜素、可溶性糖的含量，但有降低维生素Ｃ和钙、镁含量的趋势     

Water requirement,yield and fruit quality of grapefruit irrigated with high-sulphate water

Summary

The effect of irrigation with different amounts of high-sulphate water on the growth and yield of grapefruit trees was studied during a six-year period. Irrigation with 600–700 mm of water over the irrigation season, corresponding to 50–60% of pan evaporation, proved sufficient for high yield. Under-irrigation increased soil salinity associated with the highly soluble salts, and reduced tree growth (girth increase and seasonal vegetative growth). Although the fruit growth of the stressed grapefruit trees was delayed and yield was reduced, total soluble solids and acid percentage of the juice were increased significantly. Irrigation with the higher amounts of high-sulphate water resulted in gypsum precipitation/dissolution and a low persistent soil salinity which could not be leached.