Effects of day length on flowering and yield production of Salicornia and Sarcocornia species

Salicornia is a new vegetable crop that can be irrigated with highly saline water, even at salt concentrations equivalent to full-strength seawater. During leafy vegetable cultivation, the onset of the reproductive phase is an undesired phenomenon that reduces yield and quality and prevents year-round cultivation. Knowledge about the regulation of floral induction in the members of the tribe Salicornieae, however, is lacking. To establish year-round cultivation, we studied the flower induction of five Salicornia and two Sarcocornia varieties. Plants were grown under two day lengths, 13.5 h and 18 h, and harvested by a repetitive harvest regime. A 13.5-h day length prevented flower induction in the Israeli Salicornia varieties, but a longer day length was required to prevent flower induction in two species originating from more northern latitudes. The onset of the reproductive phase under suboptimal short day length conditions severely reduced vegetative growth and yields in Salicornia. In Sarcocornia, the repetitive harvest regime prevented flowering, making it a promising candidate for year-round cultivation. Irrigating the plants with full-strength seawater (electrical conductivity 48 dS m⁻¹) vs. water with moderate salinity (electrical conductivity 10 dS m⁻¹) did not change the general flowering pattern of the studied Salicornieae members.     

Effects of supplementary pollination on cropping success and fruit quality in pistachio

The effects of pollen supplementation in pistachio orchards using an electrostatic pollination device were investigated in a 3‐year study (1996‐98) in San Joaquin Valley, California, USA. Both yield and fruit quality (per cent split fruit) were tested in several experiments. Applying smaller amounts of pollen (1.5 g per tree in early application only in 1996 or 0.5 g in two applications in 1997) resulted in higher yields than with open pollination or supplementary pollination using larger amounts of pollen (1.5 g per tree in four applications in 1996 or 1.0 g in two applications in 1997). Applying 1.0 g pollen in two applications in 1998 resulted in decreased yields compared with open pollination or non‐electrostatic pollination. Pollen germinability on the stigma was greatest for open pollination suggesting that overloading the stigmas with pollen in supplementary pollination may not only reduce yield but also increase competition between pollen grains. The per cent split fruit significantly increased only once in 1996. When pollination is a limiting factor, electrostatic pollination of pistachio can increase yield and may even increase fruit quality. However, when pollination is not a limiting factor, electrostatic pollination may even reduce yield.     

Estimate of genotypic value: A proposed method

Summary Genotypic differences in yield between breeding lines or cultivars may be estimated with the aid of functions of the regression of their individual yields, in different environments, on the mean yields of all the lines tested in the respective environments.     

Contribution of nitrogen fixed by Azospirillum to the n nutrition of spring wheat in Israel

Acetylene reduction activity (ARA) was measured in cores containing roots of various Israeli wild and cultivated wheat lines colonized by Azospirillum. The inoculated plants were grown under greenhouse or field conditions. Although, no measurable ARA was detected during earlier stages of wheat development, 50–600 nmol C₂H₄ g^?1 dry root h^?1 was measured during heading and flowering stages. By using N yield balance and ¹⁵N dilution techniques, it was found that Triticum aestivum cv. Miriam inoculated with Azospirillum accumulated 20% more N (¹⁴N and ¹⁵N) at the booting stage than did the uninoculated control. This difference in N content became less apparent in grains. No significant ¹⁵N dilution could be found and the contribution of atmospheric N₂ to the N content of grains of inoculated plants was negligible. It was concluded that the potential contribution of biological N₂ fixation to spring wheat cultivation in Israel is very low.     

Paleosols of the southern coastal plain of Israel

Paleosols of the S coastal plain of Israel were studied in a characteristic sequence situated in the Ruhama badlands area. At the upper part of the sequence, there is a Loessial Arid Brown Soil (Calciorthids), characteristic of the mildly arid climate of the area. The soil has two calcic horizons and four clayey layers alternating with four calcareous layers which are beneath them. Physical, chemical, and magnetic‐susceptibility data and micromorphological evidence indicate that each clayey layer together with the calcareous layer beneath it forms a single pedogenic unit. These units are similar to modern Grumusolic soils (Xeric Paleargids or Xererthic Calciargids) that occur in the semiarid belt of the S coastal plain and develop on eolian‐dust parent material. The calcareous layers are in fact calcic horizons formed by leaching of the carbonates from the clayey layers and accumulated in the form of in situ carbonate nodules. The leaching of the carbonates is not complete; they were never completely leached in the past. This feature together with a typical brown color is also characteristic of the modern soils developed in the semiarid water regime of the area. The four superimposed paleosols represent four cycles. It is suggested that they were formed in two phases. During a dry environment, a short phase of rapid eolian‐dust accumulation prevailed, followed by a stable phase of soil development in a somewhat wetter climate. Dating by optically stimulated luminescence and previous dating by ¹⁴C in the area suggest that the upper two paleosol cycles belong to the Last Glacial period whereas the other two cycles are of an earlier age. The magnetic‐susceptibility values decrease with age and react different from temperate areas. Below the four cycles, two totally leached paleosols developed on sandy parent material occur. Both paleosols have a reversed magnetic polarity and are hence older than 780 ky BP. The upper one is a Brown Mediterranean soil, and the lower one is a Red Mediterranean soil. Thin‐section evidence suggests that they formed on terrestrial sand dunes.     

Effect of seawater concentration on the productivity and nutritional value of annual Salicornia and perennial Sarcocornia halophytes as leafy vegetable crops

The halophyte Salicornia was recently introduced as a fresh vegetable crop that thrives in extreme salt conditions. Two annual Salicornia and two perennial Sarcocornia ecotypes were investigated for yield production and nutritional value in response to different seawater concentrations in the irrigation solution. A harvest schedule based on a three-week cycle gave better productivity than a two-week or a four-week cycle. Total yield declined with increasing percentage of seawater above 50% in the irrigation water, however annual plants had always ca 2–3-fold higher fresh biomass in comparison to their perennial counterparts. Increased percentages of seawater in the irrigation solution had the following effects on ion concentrations in the shoots: no change in Ca²⁺ and Mg²⁺, a slight increase in K⁺, and marked elevations in Na⁺ and Cl⁻. Importantly, total polyphenol, β-carotene and ureides, all known for their antioxidant capacities, rose with increasing seawater percentage, findings that indicated improved nutritional values for Salicornia and Sarcocornia irrigated with high concentrations of seawater. Impressively, both the annual Salicornia and the perennial Sarcocornia ecotypes exhibited high total shoot lipid contents of up to 2.41 and 2.06 mg g⁻¹ fresh weight, respectively, which included an omega-3 fraction of 47.6 and 41.2% of the total fatty acid content. Moreover, the high fatty acid content of the annual Salicornia ecotype was not significantly affected by increasing seawater concentrations. In this study, we thus demonstrated the feasibility of cultivating Salicornia and Sarcocornia by applying a multiple harvest system and 100% percentages of seawater in the irrigation water generating economic yields with high nutritional value. The findings also showed that Salicornia and Sarcocornia leafy vegetables may attract additional interest as an alternative source of omega-3 polyunsaturated fatty acids for human consumption, even when the crop irrigated solely with seawater.     

不同土壤水势下贝莱斯芽孢杆菌B006菌剂对茄子的促生增产作用

为了明确水肥一体化灌溉系统中不同土壤水势条件下,施用芽孢杆菌B006菌剂对茄子生长及产量的促进作用,采用灌根法测定施用芽孢杆菌B006菌剂（1×10⁷ CFU·mL^-1）对盆栽茄子幼苗生长的影响。在日光温室开展两因子、两水平交互田间小区试验,在土壤水势分别为-30 kPa和-40 kPa条件下,设置施用和不施用（对照）芽孢杆菌B006菌剂共4组处理。各处理均施用278.77 kg·hm^-2化学肥料（N/P/K为17：9：34）。采用电子张力计监测土壤水势,采用水肥一体化自动灌溉系统进行灌溉。分别在移栽时和定植后30 d浇灌浓度为1×10⁷ CFU·mL^-1的B006菌剂稀释液。35 d后测定茄子的株高、茎粗、叶绿素含量和地上部干质量,50 d后调查茄子开花数,每次施肥前测定土壤速效氮、磷、钾含量,收获期测定产量,收获后测定根长和根干质量。结果表明：施用B006菌剂处理的盆栽茄子株高、茎粗、根长和根干质量比对照分别提高了16.7%、20.7%、28.7%和67.0%。在日光温室大棚试验中,施用B006菌剂处理土壤的速效磷、速效钾含量均低于对照;土壤水势-30 kPa和-40 kPa条件下,施用B006菌剂处理的茄子产量比对照分别提高了24.5%和18.1%。当灌溉量从804.88 m³·hm^-2减少到574.91 m³·hm^-2时,施用B006菌剂的两处理之间产量无显著差异。综上所述,施用芽孢杆菌B006菌剂可以促进茄子对氮、磷、钾的吸收,提高肥料利用率,从而促进植物生长,甚至在少水灌溉条件下不降低茄子产量。