Evaluation of garlic cultivars for salinity tolerance

Salinity tolerance in garlic cultivars was studied in pots. A 50% yield reduction occurs at 5.60-7.80 dS m1, depending on genotype. It was estimated that if soil salinity exceeds 1.70 dS m_l, the mean garlic yield declined by 1.68% per unit increase in soil salinity.     

番茄疫霉根腐病的发生与防治技术

番茄疫霉根腐病,俗称＂烂脖根死棵病＂.近几年此病发生危害有逐年加重趋势.尤其是冬春茬和早春茬番茄,在4-5月份结果初期发病严重,死棵多,甚至毁秧绝产.此病发生期与辣椒疫病发生期基本相同,其危害程度也不相上下.     

波兰樱桃产业发展概况

介绍了波兰的樱桃产量、面积和分布,主要品种和栽培模式,为中国的樱桃产业发展提供了系统的产业信息。     

Growth rates of glasshouse tomato fruit in relation to final size

The individual growth rates of the first five tomato fruits on 25 trusses of similar age within a crop grown in commercial glasshouse conditions were assessed from anthesis to ripening during April and May. Final size of fruit at ripening was proportional to the maximum rate of increase in fresh weight, about 40 d after anthesis, and related to the maximum rate of increase in diameter, between 15 and 20 d after anthesis, even though ripe fruit fresh weight varied from 20 g to over 100 g. On any one truss these fruit ripened within the same week, regardless of fruit size and prevailing growth rate. These findings suggest that final size was related to the peak fruit growth rate rather than the duration of development. A high growth rate late in development did not delay fruit ripening. The implications for recent continuous measurements of the diameter growth rate in young fruit are discussed.     

Deposition of calcium compounds in tomato fruit in relation to calcium transport

The deposition of calcium in tomato fruit grown at a range of salinities (electrical conductivities between 3 and 17 mS cm“1), with or without IAA-transport inhibitor treatment, was investigated. Calcium (Ca) in the flesh and pulp of tomato fruit was sequentially separated into four fractions: FI soluble in water, FII soluble in 2.5 mol dm“3 NaCl, Fill soluble in 2% acetic acid and FIV soluble in 5% HC1. In mature fruit, grown at 3 mS cm“1, more than half the Ca was in FI, and the Ca concentration was higher in the pulp than in the flesh. FII and Fill each contained less than 20% of the Ca, and the Ca concentration was higher in the flesh than in the pulp. In general, salinity reduced the concentration of Ca in all fractions and slightly altered the proportional distribution of Ca in fractions. The deposition of calcium in young fruit, grown at 3 and 8 mS cm“1, was highest in FII in the flesh or in FI in the pulp. When 45Ca was supplied to detached fruit, the patterns of45 Ca distribution in the fractions were similar to that of total Ca. Treatment with an IAA-transport inhibitor, CME, reduced both the uptake and transport of 45Ca. While the amount of 45Ca in all fractions was significantly reduced by CME, the proportional distribution of 45Ca among fractions was not affected substantially. Although the proportional deposition of Ca in different fractions was not significantly affected by either salinity or CME, further reduction of the intrinsically low deposition of Ca in FII of distal pulp caused by these factors may be the cause of blossom-end rot in tomato fruit.     

Relationship between lodging,morphological characters and yield of tomato cultivars

Experiments were carried out in the early and late seasons in the rain-forest zone of Nigeria to find out the relationship between lodging, morphological characters and yield of tomato. Lodging was associated with plant height, leaf area, number of branches/plant and fruit yield. Lodging was more severe in the wet early season than in the late season.     

Effect of interplanted rice on the growth of tomato in deep solution culture and on the response to salinity

Summary

Tomatoes were grown for 66 d in deep solution culture (a) without aeration, (b) with interplanted rice and (c) with air bubbled through the solution, in factorial combination with two electrical conductivities (4 and 8 mS cm^?1). Root growth was seriously restricted in the poorly aerated solutions (a) and (b). Interplanted rice stimulated shoot growth compared with the un-aerated treatment, and increased the total dry weight, leaf area and fruit yield (fresh weight) by up to 26, 34 and 22% respectively. The total dry weight of plants grown with rice was only 60% of that of the aerated ones but the area of corresponding upper leaves was 73%. Water and nutrient uptake were reduced by poor aeration but, after allowing for the uptake by the interplanted rice, only the uptakes of P and Ca by tomatoes in that treatment were significantly higher than those of the un-aerated plants. The higher salinity reduced growth and the uptake of nutrients. No interaction between aeration and salinity was found.     

Photosynthesis of field-grown Arracacha (Arracacia xanthorriza Bancroft) cultivars in relation to root-yield

There has been limited research on measuring potential differences in leaf gas exchange of Arracacha (Peruvian parsnip, Arracacia xanthorriza Bancroft) cultivars, as affected by different environments, as well as its relation to storage root-yield. The present paper reports field measurements of leaf CO₂ assimilation rates (A) for five contrasting cultivars grown at two different high-altitude locations. Using a design of plots chosen at random with three repetitions, commercial root production was determined in the two locations at different altitude (1580 and 1930 m). Daily leaf gas exchange was repeatedly monitored with a portable open-mode infrared gas analyzer at different times in both locations during the growth cycle. Root-yield, leaf area and dry weight were measured. Significant differences in leaf photosynthetic rate and in specific leaf area (SLA) were observed among cultivars. Cultivars with high SLA, had high CO₂ assimilation. Mean (A_n) and total (A_tot) of CO₂ assimilation and SLA were significantly correlated with storage root-yield across cultivars and locations. The three cultivars with the greatest commercial root production also had the highest maximum values for A and the highest specific leaf area, indicating that these two parameters can be used to select for highly productive cultivars of A. xanthorriza.     

Utilization of correlation network analysis to identify differences in sensory attributes and organoleptic compositions of tomato cultivars grown under salt stress

In tomato production, salt stress is applied to improve the fruit quality. The change in sensory attributes and organoleptic compositions in salt-stressed tomato fruits have been extensively studied; however, little is known about their interaction with each other. Correlation network analysis provides a visual representation of biological systems and useful knowledge for metabolic data analysis of tomato fruits. The aim of this study is to identify the cultivar differences in sensory attributes and organoleptic compositions of tomato fruits grown under salt stress and to elucidate their interaction among different cultivars using correlation network analysis. Salt stress was applied by adding 100 mM NaCl to the nutrient solution. Fruits were harvested at red-ripe stage and used for the evaluation of sensory attributes such as sweetness, sourness, umami, and tomato like, and organoleptic compositions such as sugar, organic acid, amino acid, and sodium ion contents. Almost all of the sensory attributes and organoleptic compositions of the fruit were significantly high in salt-stressed cultivars compared to non-stressed cultivars, and significant differences were also observed among cultivars. The correlation network analysis of the control fruit showed that compared to other traits, sugar is one of the key traits for improvement of tomato fruit quality based on high connectivity and betweenness centrality. In contrast, a high degree of positive connectivity was not observed between organoleptic compositions and sensory attributes in the salt-stressed fruit network. These results indicate that the relationship between sensory attributes and organoleptic compositions in fruits were different between the control and salt-stressed cultivars, suggesting that the salt-stressed fruit may have a different circuit of relationship compared to control. Furthermore, based on the increase ratio (salt stress/control) network results, we suggest that the increased sugar, organic acid, and amino acid contents may have contributed to the salt stress-induced enhancement of sensory attributes.     

Genetics of resistant to tomato yellow leaf curl virus in tomato

The genetics of resistance to tomato yellow leaf curl virus (TYLCV) were studied in TYLCV-resistant lines developed by crossing wild species of Lycopersicon pimpinellifolium, L. hirsutum and L. peruvianum resistant to TYLCV with susceptible L. esculentum cv. Special Back. Crosses between TYLCV-resistant lines derived from the same wild species produced progenies similar to their parents in their level of resistance. However, progenies from interspecific crosses showed greater resistance than either parent suggesting that the genes for TYLCV resistance contributed by different wild species are probably not the same (non-allelic). The gene action for TYLCV resistance also varied with the source of resistance. Analysis of F₁, F₂ and BC populations for lines derived from L. pimpinellifolium showed that resistance to TYLCV in these lines is a quantitative trait with some dominance.     

Effect of combined water and salinity stress factors on evapotranspiration of Sedum kamtschaticum Fischer in relation to green roof irrigation

In dryland areas, secondarily treated municipal wastewater could be used in extensive green roof systems. In this study, the effects of water and salt stress on a crassulacean acid metabolism (CAM) plant, Sedum kamtschaticum Fischer, was evaluated under intermittent saline irrigation. The salinity of irrigation water varied from 6.0 to 18.0 dS m^?1. A reduction in soil water content and an increase in soil water electrical conductivity (EC) were observed during the irrigation interval (5–17 d) as a result of evapotranspiration (ET). The effect of soil water potential (SWP) on reduction of the ET ratio (ET_r) was successfully described with an equation that could be applicable to a wide range of soil salinities and water contents, to estimate ET. In this study, the stress factor was defined as the integration of solute potential, and matric potential less soil water content for optimum growth (less than ?0.1 MPa) with elapsed time. The stress factor rapidly reduced total ET in CAM plants but effectively increased water-use efficiency (WUE). Thus, by using CAM plants for green roofs under intermittent saline irrigation, the need for irrigation water is reduced without a considerable loss of plant biomass.     

The effectiveness of grafting to improve tomato fruit quality

The possibility of applying grafting to improve fruit quality has been scarcely investigated. Different shoot tomato (Solanum lycopersicum) genotypes were grafted onto distinctly-different tomato rootstocks and the effect of the rootstock on two important fruit quality parameters, soluble solids content (SSC) and titratable acidity (TA), was studied under both non-saline and saline conditions. Increased SSC and TA in fruits from grafted plants grown under saline conditions were observed on different grafting combinations. One of these rootstocks (cv. Radja) was able to induce increases in both fruit yield and fruit quality traits of the scion. When recombinant inbred lines (RILs) from the crossing of the cultivated tomato and wild tomato (Solanum cheesmaniae) were tested as rootstocks, using the commercial hybrid ‘Boludo’ as scion, the rootstock also improved SSC and TA when grafted plants were grown under non-saline conditions. On the whole, these results show the effectiveness of grafting with respect to upgrading of fruit quality in tomato, which is of great importance as grafting is a rapid and efficient alternative to achieve this goal.     

The interaction of a dormancy-breaking cold treatment,ancymidol, and ethephon in relation to stem elongation and flower production of Lilium cultivars

Stem elongation of Lilium cultivars ‘Black Beauty’, ‘Jamboree’ and ‘Nutmegger’ was lessened by treating the bulbs with ancymidol (10 p.p.m.) or ethephon (500 p.p.m.). Ancymidol was the more effective inhibitor of stem elongation, although applied at a much lower concentration. Application of the growth regulators prior to a dormancy-breaking cold treatment provided more effective control of stem elongation than post cold-treatment application. The total number of flowers and the number of secondary flowers per stem of ‘Black Beauty’ and ‘Nutmegger’ were increased by treating the bulbs with ancymidol. However, unlike the optimal time for lessening stem elongation, enhancement of flower production was greatest when ancymidol was applied after completion of the cold treatment. Ethephon was unsatisfactory, since it inhibited flower production by ‘Black Beauty’ and ‘Nutmegger’, while ‘Jamboree’ was relatively insensitive to it, as indicated by a lack of inhibition of flower production and a small degree of inhibition of stem elongation.     

The response of poinsettia cultivars to auxins in root promotion of stem cuttings

Terminal stem cuttings of 9 poinsettia cultivars were pretreated with auxin compounds either singly or in combination prior to rooting in both the winter and summer. The 9 cultivars responded similarly to the auxin containing chemicals with the dual treatment of a liquid dip into either Jiffy Grow at 1 000 ppm or Chloromone at 750 ppm followed by a powder dip with Hormodin No. 2, most effective in stimulating rooting in all cultivars studied except ‘Marble Annette Hegg’. In the winter, the combination treatment of Jiffy Grow at 1 000 ppm and Hormodin No. 2 significantly increased rooting over the separate application of these chemicals, whereas in the summer there was an increased benefit of dual treatment only with ‘C-1 Red’ and ‘Annette Hegg Supreme’. Those cultivars such as ‘C-1 Red’ and ‘Ecke White’ which produced a low number of roots and fresh weight without root promoters, responded most to auxin root promoters.     

宁夏黄瓜新品种及主栽品种对白粉病的抗性评价

通过盆栽接种试验和田间自然发病调查相结合的方式进行了10个黄瓜新品种和2个黄瓜主栽品种(‘博美626‘’德尔88’)对白粉病的抗性鉴定,旨在明确不同黄瓜品种对白粉病的抗性水平,为黄瓜抗病品种的筛选和农业防治提供科学依据。试验结果表明,除‘德尔100’易感白粉病外,其他11个品种均对白粉病具有不同程度的抗性,其中‘津早3号‘’粤青1号‘’德尔80‘’德尔11‘’德尔12’达到高抗,而宁夏主栽品种‘博美626‘’德尔88’只达到中抗;从不同黄瓜品种生长指标和产量测定结果来看‘,德尔11‘’德尔80‘’津早3号’均表现出了优势,其产量均高于主栽品种,而‘德尔12‘’粤青1号’长势相对较差,产量低于主栽品种。总体来讲,新品种‘德尔11‘’德尔80‘’津早3号’在宁夏具有推广价值,可进一步进行大面积试验示范。     

草莓品种对蚜虫的抗性机制

为探讨草莓品种对蚜虫的抗性机理,以5个常规草莓品种为试材,通过调查、测定大棚内蚜虫自然发生动态和室内人工接虫后种群变化,并对草莓叶片的形态学和生理学特性与抗蚜性的关系进行了分析。结果表明章姬对蚜虫高感,丰香感,卡姆罗莎和吐德拉抗,弗吉尼亚高抗。草莓品种对蚜虫抗性与叶片背面的茸毛密度成正相关,与气孔密度呈显著负相关;与叶片的木质素含量成正比;与酚类物质含量无显著关系,与总游离氨基酸、可溶性固形物含量和水分含量无明显的线性关系。但草莓对蚜虫的抗性程度与叶片中脯氨酸、缬氨酸和胱氨酸的含量有关,特别是缬氨酸和胱氨酸在感蚜品种中的含量是抗蚜品种中的2～3倍。     

The cold requirement of tulip cultivars

Results of 8 years of trials have been used to assess the cold requirements of 116 tulip cultivars, expressed as the number of days of cold (9°C) required to produce flowers in 21 days at 18°C. The data are compared with commercial recommendations for the dates of transferring tulips to the glasshouse for forcing.     

Yield,blossom-end rot incidence,and fruit quality in pepper plants under moderate salinity are affected by K and Ca fertilization

One of the most important factors limiting agricultural expansion and production is the restricted supply of good quality water. The present study examines the effects of K⁺ and Ca²⁺ fertilization on sweet pepper production, blossom-end rot (BER) incidence and fruit quality of pepper plants (Capsicum annuum L.) grown under moderate saline conditions. Pepper plants were grown in a controlled-environment greenhouse under hydroponic conditions with different nutrient solutions obtained by modifying the Hoagland solution. The experiment consisted on four K⁺ treatments (0.2, 2, 7 and 14 mM) +30 mM NaCl, and four Ca²⁺ treatments (0.2, 2, 4 and 8 mM) +30 mM NaCl, having in common a control without salt with 7 mM K⁺/4 mM Ca²⁺. Salinity decreased total fruit yield and marketable fruit yield by 23% and 37%, respectively. The marketable fruit yield reduction by salt treatment was mainly due to the increase in the number of fruit affected by BER. This typical physiopathy of the pepper fruits occurred between 18 and 25 days after anthesis (DAA), when the highest fruit growth rate was reached. Fruit quality parameters were also affected by salt treatment where the fruit pulp thickness and firmness were decreased, and fructose, glucose and myo-inositol fruit concentrations increased with salinity relative to fruits from control treatment. Under saline conditions an increased supply of K⁺ reduced the fruit fresh weight, the percentage of BER and the marketable yield although promoted the vegetative growth. However, increasing Ca²⁺ concentration in the nutrient solution increased the fruit production, and the marketable yield as consequence of decreasing the percentage of fruit affected with BER. Fruit quality parameters also were affected by the K⁺ and Ca²⁺ treatments.     

Phytochemical composition and antioxidant activity of high-lycopene tomato (Solanum lycopersicum L.) cultivars grown in Southern Italy

In this study, the antioxidant components and of six high-lycopene (Lyco 1, Lyco 2, HLY 02, HLY 13, HLY 18 and Kalvert) and one ordinary (Donald) tomato cultivars (cvs) grown simultaneously in an open-field of the Southern Italy were investigated. Lycopene, β-carotene, lutein, total phenols, flavonoids, ascorbic acid (AsA), dehydroascorbic acid (DHA) and total vitamin C (AsA + DHA) contents, as well as hydrophilic and lipophilic antioxidant activities (HAA and LAA) were determined. Significant differences were detected among tomato cvs in all studied antioxidant components, as well as in the antioxidant activity of their hydrophilic and lipophilic fractions. High-lycopene tomato cvs showed higher lycopene, β-carotene, HAA and LAA when compared to cv Donald. Cv HLY 18 showed the highest lycopene and β-carotene content with 232.9 mg/kg fresh weight (fw) and 19.4 mg/kg fw, respectively. Except for Kalvert, high-lycopene tomato cvs also obtained higher total vitamin C levels, with cv HLY 13 top ranking with an average of 352.8 mg/kg fw. LAA ranged from 133.5 μM Trolox/100 g fw in cv Donald to 540.1 μM Trolox/100 g fw in cv Lyco 2 and was significantly correlated to lycopene (r = 0.53; p < 0.01) and β-carotene (r = 0.56; p < 0.01) contents. A variation between 2.7- and 4.0-fold was found in LAA of high-lycopene tomato cvs compared to Donald. HAA was significantly correlated to the amount of DHA (r = 0.61; p < 0.01) and total vitamin C (r = 0.60; p < 0.01). Although these data require confirmation over a longer period of time, this investigation suggests a promising use of the high-lycopene tomato cvs for the production of tomatoes with higher nutritional quality.     

Genotypic variation in the response of pepper to salinity

Using 102 pepper (Capsicum annuum) genotypes, a greenhouse experiment has been conducted to study genotypic variation in tolerance to 100 mM sodium chloride (NaCl) in nutrient solution. Based on the severity of leaf symptoms caused by the NaCl treatment there was a substantial genotypic variation in salt tolerance. From this screening experiment, six sensitive and six tolerant genotypes were chosen to study dry matter production and root and shoot concentrations of sodium (Na), potassium (K) and calcium (Ca) in a growth chamber experiment in a nutrient solution with and without 150 mM NaCl. The genotypes selected as sensitive were highly damaged and developed severe chlorosis and necrosis under NaCl treatment, while the genotypes selected as tolerant were slightly affected. On average, decreases in shoot dry matter production caused by NaCl were greater in the sensitive than the tolerant genotypes. Application of salt increased shoot Na concentration at greater amount in the sensitive than the tolerant genotypes. Of the tolerant genotypes, the genotype Cac (Capsicum annuum var. cerasiforme) and 1245 F1 had around 2.45% Na in shoot while the sensitive genotypes Kandil and Pazarcik contained, on average, 5.4% Na. All sensitive and tolerant genotypes exhibited more or less similar shoot concentrations of K and Ca. There was very significant and positive correlation between severity of leaf symptoms and shoot Na concentration, but no correlation could be found in the case of K or Ca concentrations with the severity of leaf symptoms. The results indicate existence of substantial genotypic variation in tolerance to NaCl stress in pepper. It seems very likely that exclusion of Na from roots into growth medium plays a critical role in expression of high Na tolerance in pepper.