Effects of suboptimal low temperature on yield,fruit appearance and quality in muskmelon (Cucumis melo L.) cultivars

Summary

The effects of suboptimal low temperature were investigated on an array of yield, fruit appearance and fruit quality characters in 23 cultivars of melon, Cucumis melo L. The cultivars were grown in two temperature regimes: (I) a heated greenhouse (T1) with temperatures similar to those used in commercial cultivation in the winter in Israel; and (ii) an unheated greenhouse (T2) that had significantly lower night temperatures than T1. Significant differences were found among the cultivars in all characters. Plants from T2 showed an extended fruiting period, more fruits and higher total yield but smaller and lighter fruits than in T1. Fruits from T2 also had significantly more netting and higher amounts of total soluble sugars (TSS), sucrose and fructose than fruits from T1. Hybrid cultivars showed significantly higher electrical conductivity (EC), pH, acidity, TSS, sucrose, fructose and total sugars than open pollinated cultivars. Three trends were found among the characters in respect to the performance of the cultivars between T1 and T2: (a) most cultivars had significantly higher amounts in T2 than T1 (fruit/plant, yield/plant and fructose); (b) only cultivars with amounts below the pooled mean in T1 had higher amounts in T2 (percent dry weight, sucrose, TSS and total sugars); (c) no trend was found between T1 and T2 (mean fruit weight, pH, EC, glucose). Suboptimal low temperatures, when used appropriately, can aid in improving fruit quality.     

日光温室樱桃番茄品种比较试验

为进一步丰富东海县及周边地区樱桃番茄品种,满足消费者多样性需求,充分发挥新品种在农业增效、农民增收中的作用,通过选取11个樱桃番茄品种进行越冬试验示范,对果实性状、产量等指标进行了比较。结果表明：绿宝石口感好、产量最高,667 m2产量较对照平均增长86.00%,但裂果较重,平均裂果率达19.2%;凤珠口感好,667 m2产量比对照平均增长29.27%,但果形不整齐;釜山88口感好,果形圆整,667 m2产量比对照平均增长7.99%;航黄樱1号、航黄樱2号在黄色品种中口感好,667 m2产量分别较对照增加2.60%、18.28%。这5个品种表现比较稳定,适宜在连云港地区推广种植。     

塑料大棚早春茬结球甘蓝新品种引进筛选

摘要：为筛选出适宜静宁县塑料大棚早春茬种植的结球甘蓝新品种,以当地主栽品种极早绿为对照, 对新引进的15个结球甘蓝新品种进行了系统的品种比较试验。试验结果表明：豪绿75、中甘W137、中甘 106这3个品种叶球近圆形、叶球绿色、中心柱低、叶球紧实、单球质量高、病虫害发生率低;豪绿75产量 最高,为69 125.00 kg/hm2 ,较对照增产32.77%,其次为中甘W137、中甘106,分别增产30.25%和14.79%; 从生物学性状、丰产性、抗病性等指标综合评价,上述3个品种表现突出,优于其他参试品种,适宜当地塑 料大棚早春茬推广种植。     

早春塑料大棚甜椒品种比较试验

为筛选出适宜晋中地区早春塑料大棚种植的甜椒品种,特收集9个新选育的甜椒品种进行比较试验,且以欧美特为对照,对品种的植物学性状、果实商品性、产量、抗病性等指标进行比较分析。结果表明：方兴065、方兴九号和晋椒201这3个品种适宜晋中地区早春塑料大棚种植,其中方兴065畸形果率最低,产量最高,667 m²产量6 526.04 kg,比对照增产12.98%;晋椒201单株结果数最多,植株生长势最强,667 m2产量6 410.94 kg,比对照增产10.99%;方兴九号综合抗病性最强,果实商品性好,667 m²产量6 393.23 kg,比对照增产10.69%。     

Observations on the Effect of Potash Supply on the Tension of the Tracheal Contents in Fruit Trees and Bushes

Summary

The effects of pollen source on fruit set and fruit quality characteristics (xenia effects) were examined in three commercial cultivars of mandarin, Imperial, Ellenor, and Murcott. Six trees of each cultivar received six pollination treatments: three cross-pollen sources, self-pollination, bagging and bagging with emasculation. Pollen tube growth, percentage fruit set, fruit weight, seediness, sugar and acid content were assessed in all treatments. Significant xenia effects, including effects on sugar content, were found in all cultivars. `Imperial' was found to be self-incompatible as self-pollen tubes were inhibited in the upper style. This resulted in a lower fruit set in self-pollinated fruits (P<0.01), a very low fruit weight (33–55 g, compared with 92–103 g, P<0.01), and fruits containing few or no seeds. In addition, `Ellenor' and `Murcott' pollen significantly increased sugar content of fruit by between 0.9–1.6% compared with self-pollinated and unpollinated treatments (P<0.05). Widespread problems of variable production and poor fruit quality in `Imperial' may be alleviated by interplanting with appropriate pollen sources such as `Ellenor' and `Murcott'. Pollen source significantly affected fruit set, seed number and sugar content but not fruit weight of cv. Ellenor. In particular, `Murcott' pollen produced a significantly higher fruit set, relatively low seed number, and the highest mean sugar content (13.2%), significantly higher than `Imperial' pollen, bagged, and unpollinated treatments (>12.5%, P<0.01). Fruit production, seediness and sugar content of `Ellenor' mandarin may be improved by interplanting with `Murcott'. Cross-pollination significantly increased seed number of `Murcott' (15–21 seeds per fruit, compared with 13–17 seeds per fruit, P<0.01). `Murcott' could be planted in pure blocks since self-pollinated `Murcott' fruit had slightly fewer seeds than crosses, without any significant loss of size or quality. These results demonstrate the need for careful consideration of interplanting of cultivars and management of pollinators such as the honeybee, Apis mellifera L. to maximize fruit production and quality in mandarins.     

辣椒新品种比较试验

以引进的5个辣椒新品种为试材,对辣椒品种的生育期、抗病性、产量等指标进行了比较试验,以筛选适合在通辽地区栽培的辣椒新品种。结果表明：蒙科红九号综合评价最好,667m²产量为2 640.12 kg,显著高于对照,且抗病性强、果大、果色好;蒙科红十号抗病性、抗倒伏及耐旱性均较强,蒙科红十号667 m²产量为2 326.56 kg,显著高于对照。综合来看,蒙科红九号、蒙科红十号适合在通辽地区栽培,其他供试品种在生长特性、产量、抗性等方面表现不佳,但可作为育种资源,进行后续杂交种选育。     

Combinations of GA3 and AVG delay fruit maturation,increase fruit size and improve storage life of `Feicheng' peaches

Summary

Different concentrations of aminoethoxyvinylglycine (AVG) and gibberellic acid (GA₃) and their combinations, applied at two stages of fruit growth, were evaluated for prolonging the marketing season of `Feicheng' peaches. GA<sub>3</sub> applied at the end of pit hardening, or AVG applied two weeks before commercial harvest, inhibited fruit maturation on the tree, delayed harvest and reduced flesh browning after cold storage in a concentration-dependent manner. A synergistic effect was found when both GA<sub>3</sub> and AVG were used, with the combination of 100 or 150.mg l<sup>±1</sup> GA<sub>3</sub>, applied at the end of pit hardening, and 100 mg l<sup>±1</sup> AVG, applied two weeks before harvest giving the best results. These combinations retarded the change in ground colour, loss of firmness, and reduction in acidity by 2±3 weeks. Since harvest was prolonged by 2±3 weeks, soluble solids content (SSC) in fruit increased compared with the control (harvested earlier). Fruit size was significantly greater on treated trees compared with the controls when fruit set was controlled to the same level by hand thinning. After four weeks of storage and 4.d at 208C, 83% of control fruit developed tissue browning, but only 5% of AVG + GA<sub>3</sub>-treated fruit developed browning after six weeks of storage and 4 d at 208C. Thus, the marketing season of `Feicheng' peaches was prolonged by at least four weeks by 100 or 150 mg l^±1 of GA₃ and 100 mg l^±1 of AVG. Fruit treated with 150 mg l^±1 GA₃ plus 100 to 150 mg l^±1 AVG showed similar results but failed to ripen properly after cold storage.     

The relationship between yield and assimilate supply in lychee (Litchi chinensis Sonn.)

Summary

Experiments were conducted on lychee (Litchi chinensis Sonn.) in subtropical Australia (lat. 27° –29°S) to evaluate the role of assimilates on fruit retention. All the leaves of the last flush, all the leaves of the previous flush (about eight leaves per terminal shoot), or all the old leaves were removed from trees. Medium (3–5.cm diameter) or large branches (5–10.cm diameter) were girdled and defoliated after fruit set, and fruit retention compared with ungirdled and undefoliated branches. Other branches were girdled and defoliated between anthesis and fruit harvest. Finally, 20, 50 or 80% of the flowering panicles were defruited on large trees. Defoliated trees had 35 to 45% lower yields than the controls. This was despite the treatment with all the old leaves removed having a much lower leaf area index than the other defoliation treatments (1.7 vs. 2.3 and 2.8). Leaves next to the inflorescences are more important for yield than the older leaves. Fruit retention was very low on girdled branches that had been defoliated, especially when the leaves were removed in the first 20.d after anthesis. This suggests that the yields of girdled branches were determined by the availability of assimilates soon after fruit set. In contrast, the number of fruit retained on ungirdled branches was unrelated to the number of leaves, with defoliation having no effect on yield. Fruit on these branches were supported by resources from elsewhere in the tree. Thinned trees had similar yields to those of unthinned plots (65–82.kg tree^–1). Thinning apparently increased fruit retention in the remaining clusters, under a higher leaf:fruit ratio. There were large differences in the concentrations of starch in the tree, and seasonal changes, with starch declining from flowering to fruit harvest. In contrast, there were only small responses to the treatments, suggesting that the fruit were mainly dependent on current photosynthesis. Photosynthesis in the leaves behind the fruit clusters was more important than photosynthesis in the older shaded leaves.     

Effect of methyl jasmonate on resveratrol production in organs and cell suspension cultures of two Iranian grapevine (Vitis vinifera L.) cultivars

Summary

Resveratrol (3,5,4'-trihydroxy stilbene) is a polyphenolic compound that prevents cancer, as well as heart and vascular diseases in humans. In our previous study, this compound was extracted primarily from the fruit of 147 Iranian grapevine cultivars and determined by High Performance Liquid Chromatography (HPLC). Among these cultivars, the two most desirable (‘Rajabi Sefid Shiraz’ and ‘Keshmeshi Ghermez’) were selected for the present study and the amounts of resveratrol in their leaves and fruit were measured. Levels of resveratrol in the fruit of both cultivars were higher than in their leaves, and samples treated with 1.0 mM methyl jasmonate produced more resveratrol than the untreated controls. Leaf or fruit callus and cell suspension cultures of both cultivars were established and the levels of resveratrol produced were determined. Calli were produced from leaf and fruit explants after 4 weeks and 6 weeks in culture, respectively. Cells derived from calli of both types of explant were then established in suspension culture after three sub-cultures and also produced resveratrol. Cell suspensions were treated with 0.1 mM methyl jasmonate 6 d after the third sub-culture, when they had entered the exponential growth stage. The levels of resveratrol produced by methyl jasmonate-treated cells were significantly higher than those in plant organs or in untreated control cells.     

有机番茄品种比较试验

选取8个番茄品种在延庆地区进行有机生产,通过生育性状、抗病性、产量、品质的对比分析,筛选适宜延庆地区推广种植的番茄品种。结果表明:参评的8个番茄品种中,1315、17504与仙客8这3个品种的生物性状表现与产量、果实品质水平较高,均适合在延庆地区推广,其中以1315品种的试验结果最优,仙客8与17504这2个品种可以作为推广过程中的有益补充。     

Effect of tree and branch thinning on growth,yield, and fruit quality of persimmon trees in a high-density orchard

A study was conducted to evaluate the effect of branch and tree thinning on growth, yield and fruit quality in 8-year-old non-astringent persimmon (Diospyros kaki L.f.) trees in a high-density orchard over 6 years in Korea. Adjacent trees in the rows were removed in 2008 (first-year thinning) or in 2010 (gradual thinning). Trees in the second treatment also had 25% of the main scaffold branches removed in the first two seasons. Control plots were left unthinned. First-year thinning elevated leaf macro-nutrient concentrations, increased the production of short fruiting shoots (less than 20 cm) per tree, decreased water sprout development and weight of pruned biomass, and increased fruit set compared with values recorded on control trees and with gradual thinning. First-year thinning gave higher photosynthetic photon flux in the centre of the canopy and better fruit quality. There were generally only small differences in total yield across the three treatments in individual years, but much higher total marketable yield from 2010 to 2013 in the first-year thinning plots. First-year thinning improved overall tree productivity, and the gross returns were 80% higher than those of control from 2008 to 2013 when the extra cost of the thinning was taken into account.     

樱桃番茄品种比较试验

为了筛选出陵水地区果实性状与千禧相似,并且高抗TY病毒的樱桃番茄新品种,新引进了18个新品种,以千禧为对照,进行品种比较试验。测定了早熟性、植株性状、果实性状、产量、抗TY病毒性等指标。结果表明:艳妃202、粉樱、丽妃2号、西大樱粉1号和云河5个品种抗TY性强、产量高且果实性状好,综合表现优于对照千禧,可以在陵水地区推广种植。     

Multiple Avenues to Gender in Strawberries

ABSTRACT

Common strawberry cultivars are hermaphrodites, producing both anthers and pistils in their flowers. However, octoploid Fragaria species are trioecious and different genotypes can be female with pistillate flowers, hermaphrodites, or males with staminate flowers. One female selection, F. virginiana High Falls 22 and three hermaphrodite selections, N8688, RH23, and Montreal River 10 were hybridized with five June-bearing cultivars. Seedlings of each family were planted in Ontario and Michigan. Two F. chiloensis selections Pigeon Point (female) and FRA1267 (hermaphrodite), were hybridized with 14 F. virginiana selections. Seedlings from each family were planted in Ontario and Minnesota. In all progeny, the presence or absence of anthers was recorded and a subjective scale used to estimate the percentage of fruit set (1–10 representing 10% intervals). Also, FRA1267 was crossed with one F. × ananassa selection and the progeny intercrossed and grown in Ontario. In the sib-crosses gender was recorded. In two female parents, the female progeny had on average a higher fruit set than the hermaphrodite progeny. F. virginiana genotypes varied in their fruit set, which suggested that there are a number of alleles involved in the fertility of hermaphrodites. In crosses, FRA1267 produced 80% females when used as a female parent and 100% hermaphrodites when used as a male parent. It is thought that the trait is inherited cytoplasmically or that the F. chiloensis alleles involved are epistatic when F. virginiana or F. × ananassa is used as a male parent.     

Yield and oil quality of intensively trained trees of three cultivars of olive (Olea europaea L.) under different irrigation regimes

Summary

The aim of the present study was to evaluate the qualitative and quantitative yield response to irrigation of olive in southern Italy. The olive cvs Kalamata, Ascolana Tenera, and Nocellara del Belice were tested in a factorial combination with four irrigation levels: a rain-fed control (T₀) and three treatments (T₁, T₂ and T₃) irrigated daily with an amount of 33%, 66% and 100%, respectively of crop evapotranspiration. Soil water content remained near field capacity in treatment T₃ with no difference with respect to treatment T₂. In T₀ and T₁, the soil moisture decreased during the summer with the lowest value (20.8%) found in T₀ on 12 August, after which rainfall restored the soil moisture to field capacity. During the season the relative water content in the leaves was higher in the irrigated treatments than in the rain-fed control. Yields were higher in all the cultivars with irrigated treatments than in the rain-fed control. The yield increase with treatment T₁ in `Nocellara del Belice' was 200% compared with the rainfed control and with T<sub>2</sub> in `Ascolana tenera' and `Kalamata' the yield was 233% and 47% greater than in the control. The higher oil yield obtained in the irrigated treatments was mainly due to the increase in fruit yield, since the pulp-stone ratio and the quantity of triglycerides accumulating in the fruits were similar for all treatments. The fatty acid composition of the oils was not affected by irrigation, while there was a decrease in the content of polyphenolic substances with irrigation. This decrease could be attributed to different enzymatic activity, caused by the water deficit, rather than to different degrees of fruit ripening. The decrease of polyphenols did not influence the oil quality in terms of organoleptic parameters or oil shelf-life.     

Effects of auxin application on fruit formation in tomato growing under stress temperatures in the field

Summary

Tomato (Lycopersicon esculentum L. Mill) cultivars Early Urbana and Red Clode were grown in the field at adverse temperatures (stress regimes) until they set fruit in two growing seasons (Autumn and Spring) during 1999 and 2000 in Ahwaz (Southern Iran). To test the effectiveness of auxins in enhancing fruit set, racemes of tomato were sprayed during early fruit set with 25, 50 and 100 mg l^–1 4-chlorophenoxy acetic acid (4-CPA) and indole-3-butyric acid (IBA) followed by two additional applications at three intervals. The control plants were treated with deionized water. At harvest, racemes from autumn and spring plantings that were treated with 4-CPA had more large fruits than the control racemes. In both growing seasons, neither cultivar showed a significant difference in fruit set in plants treated with IBA, compared with controls. The ratio of fruit/flower in all racemes treated with 4-CPA increased significantly compared with the other treatments. However, auxin treatments did not significantly affect the number of flowers per raceme. Plants treated with 4-CPA produced the highest yield of marketable fruit. The greatest increase in total yield and parthenocarpic fruit occurred with 4-CPA treatments. Also, there was little difference between concentrations of 4-CPA on fruit set in both cultivars. It may be concluded that the response of fruit setting in tomato to either low or high temperatures regimes was auxin dependent and that 4-CPA was more effective than IBA.     

早春大棚黄瓜新品种比较

为筛选出适合汉中地区早春大棚种植的黄瓜新品种,特引进4个黄瓜新品种进行大棚栽培比较试验。结果表明:京研优胜的综合表现最优。其始收期为4月26日,第1雌花节位为4～5节,早熟性好;株高207.1 cm,主蔓粗8.9 mm,植株长势较强;瓜长35.3 cm,瓜粗3.3 cm,单瓜质量225.0 g,瓜形呈短棒状,瓜色绿色有光泽,瓜刺密、瓜瘤中等,商品果品相好;667 m~2产量为4 216.1 kg,较对照增产4.1%,丰产性最高。可作为汉中地区早春栽培品种进行推广种植。     

Response of kiwifruit (Actinidia deliciosa cv. Allison) to post-harvest treatment with 1-methylcyclopropene

Summary

Experiments were conducted to observe the effect of different concentrations of 1-methylcyclopropene (1-MCP) on the post-harvest life and quality of ‘Allison’ kiwifruit (Actinidia deliciosa). Fruit were treated with 1-MCP at 0.5 µl l^–1, 1.0 µl l^–1, or 2.0 µl l^–1, un-treated fruit served as controls. Each 1-MCP treatment was applied for 24 h at 20°C. After treatment, fruit were transferred to ambient temperature storage (22º ± 4ºC; 65 – 70% relative humidity) for 18 d, during which time observations on various physical, physiological, and biochemical parameters were recorded at 3 d intervals. Our results indicated that 2.0 µl l^–1 1-MCP was the most effective treatment to delay softening and ripening in ‘Allison’ kiwifruit, as such fruit showed the lowest mean weight loss (9.8 ± 0.2%), the highest mean fruit firmness value (32.7 ± 0.2 N), and began to ripen only after 12 d in storage, whereas untreated fruit started ripening on day-6 of storage. The activities of fruit softening enzymes such as polygalacturonase (PG; 58.5 ± 0.3 µg galacturonic acid g^–1 FW h^–1), and lipoxygenase (LOX; 3.96 ± 1.3 µmoles linoleic acid oxidised min^–1 g^–1 FW h^–1) were lower, and total phenolics (TP) contents (24.3 ± 0.3 mg 100 g^–1) and anti-oxidant (AOX) activities (12.5 ± 0.03 µmol Trolox g^–1 FW h^–1) were higher in 1-MCP-treated fruit than in untreated fruit (PG, 98.3 ± 0.5 µg galacturonic acid g^–1 FW h^–1; LOX, 4.39 ± 1.0 µmoles min^–1 g^–1 FW h^–1; TP, 5.3 ± 0.6 mg 100 g^–1; AOX, 4.7 ± 0.02 µmol Trolox g^–1 FW h^–1, respectively). In addition, 1-MCP-treated fruit exhibited lower rates of respiration (48.3 ± 0.4 ml CO₂ kg^–1 h^–1) and ethylene production (30.2 ± 0.02 µl kg^–1 FW h^–1) than untreated fruit (58.9 ± 0.6 ml CO₂ kg^–1 h^–1; 38.7 ± 0.04 µl kg^–1 FW h^–1, respectively). Similarly, 1-MCP-treated fruit had higher titratable acidity (TA; 1.33 ± 0.3%) and ascorbic acid (AA) contents (115.9 ± 2.6 mg 100 g^–1 pulp) and lower soluble solids contents (SSC; 8.33º ± 0.2º Brix) than untreated kiwifruit (TA, 1.0 ± 0.2 %; AA, 105.3 ± 2.2 mg 100 g^–1 pulp; SSC, 13.7º ± 0.3º Brix, respectively). Thus, 2.0 µl l^–1 1-MCP can be used for the post-harvest treatment of ‘Allison’ kiwifruit to enhance its shelf-life and marketability by approx. 6 d.     

日光温室高品质中果型番茄品种筛选

为筛选日光温室高品质番茄品种，对较受欢迎的13个中果型粉果番茄品种进行筛选试验，从番茄果实性状、产量、品质及根结线虫病抗性等方面进行分析。结果表明：13个番茄品种在产量、品质和根结线虫病抗性方面均存在差异，其中金粉9号和金秋1号的产量、维生素C含量、可溶性糖含量、总酸含量均高于对照品种，分别较对照增产14.36%和11.23%；金粉9号和金秋1号抗病性好于对照，根结线虫病病情指数分别为10.00和9.26，均较对照显著降低。综合产量、品质和抗性指标，金粉9号和金秋1号表现较好，在今后试验中可以尝试示范推广。     

鲜食朝天椒品比试验

为了筛选更适合三亚地区栽培的鲜食朝天椒品种,对7个品种进行了比较试验。经过综合分析,飞艳在生育期内适应性、抗性、植物学性状、产量等方面均优于其他参试品种,产量表现极显著,667 m^2产量达2 014.3 kg,比艳红(CK)增产22.6%,为中晚熟鲜食大果朝天椒,适宜进一步推广种植。     

压砂地拱棚甜瓜新品种引进筛选试验初报

为了解和掌握不同甜瓜品种特性,筛选出适合中宁县乃至宁夏地区压砂地拱棚种植的甜瓜品种,引进甜瓜品种8个,对其生育期、果实性状及产量等指标进行测定.结果表明:银帝综合性状表现最好,产量高,糖分积累高,含糖梯度小,耐贮运,口感脆甜,商品性好;其次是抗病F-3800,产量、含糖量相对较高,耐贮运,口感脆甜;再次为创科蜜25号,...