Fruit quality and partitioning of mineral elements in processing tomato in response to saline nutrients

A sand culture experiment was conducted to study the effect of saline water on the growth and fruit quality of processing tomato (Lycopersicon esculentum Mill.) Seedlings of five tomato cultivars were transplanted in quartz‐sand pots in a greenhouse at the Agricultural Experiment Station of Sultan Qaboos University. There were four saline nutrient solutions and a control consisting of half‐strength Hoagland solution. Salinity treatments were: 50 raM NaCl + 3 mM K₂SO₄ (EC 6.75), 50 mM NaCl + 1.5 mM orthophosphoric acid (EC = 7.18), 50 mM NaCl + 1.5 mM orthophosphoric acid + 3 mM R₂SO₄ (EC 7.29), and 50 mM NaCL (EC = 5.6). Treatments were applied daily commencing two weeks after transplanting. Data were collected on growth, and fruit yield and quality. Partitioning of mineral elements was determined in the vegetative tissue. The results obtained clearly show that concentrations of total soluble solids were increased in fruits treated with saline nutrients. Dry matter content of fruits exposed to salinity were higher than those from the control plants. Fruit acidity was increased with salinity, possibly due to a lower water content and increased organic acid accumulation. In the saline treatments, sodium (Na) content was decreased when potassium (K) was applied with NaCl but Na was higher in stems followed by root and leaf tissues. The partitioning of K followed a trend opposite to that for Na but with higher content in leaves. A similar situation was observed for calcium (Ca) and magnesium (Mg). Accumulation of phosphorus (P) was the lowest among all the ions. These results indicated that survival under saline conditions was accompanied by high ion accumulation. The study confirmed that saline nutrients are important for improving fruit quality of processing tomatoes.     

Effective Bioremediation of Endocrine-Disrupting Phthalate Esters,Mediated by <Emphasis Type="Italic">Bacillus</Emphasis> Strains

Phthalic acid esters (PAEs) is a class of refractory organic compounds, widely used as additives or plasticizers in plastic industry. PAEs are ubiquitous endocrine-disrupting pollutants and can be degraded by microorganisms. The present study described the assimilation of four PAE mixture (dimethyl, diethyl, dipropyl, and dibutyl phthalate) by two bacillus species: Bacillus thuringiensis and Bacillus cereus, isolated from different agricultural soil and their consortium. Among which, the optimal degradation of 82–96% was achieved by B. thuringiensis. This is the first report on the metabolic breakdown of four basic PAE mixture. The optimum conditions for biodegradation were found to be pH 7, temperature 30 °C, inoculum size 10 mL, and concentration 400 mg/L. Moreover, the respective biodegradation followed the first-order kinetic model. Our results proffered supplementary confirmation of the wide spectrum of PAE utilization by B. thuringiensis and suggest the possibility of applying it for the remediation of PAE contamination waste.     

Salinity Stress Promote Drought Tolerance of Chenopodium Quinoa Willd

A greenhouse experiment was conducted to investigate the impact of water and salt stress in Quinoa plants (Chenopodium quinoa Willd.). Irrigation treatments using saline solutions of 0 (control), 50(T₁), 200(T₂), 400(T₃), 600(T₄), and 800(T₅) mM sodium chloride (NaCl) were adopted. The results indicated that quinoa plants can tolerate water stress (50%FC) when irrigated with moderately saline water (T₁ and T₂, respectively). Salinity stress increases quinoa drought tolerance in terms of biomass production. Neither osmotic stress nor ions deficiency/toxicity seems to be determinant under T₁ and 100%FC. Salinity induced a significant increase of sodium (Na⁺) and chloride (Cl^?), while reduced magnesium (Mg²⁺) and calcium (Ca²⁺) in stems, leaves, seed’s coating, and seeds. The potassium (K⁺)/Na⁺ ratio never fell below 1 with T₁; yet, fell to 0.78 and 0.89 with T₂ for 100% and 50%FC, respectively. The seed coat limited the passage of possibly toxic concentrations of Na⁺ and Cl^? to seed interior, as high Na⁺ and Cl^? was found in the seed coat.     

Zinc biofortification in rice: leveraging agriculture to moderate hidden hunger in developing countries

A restricted dietary range and a deficit of essential minerals such as zinc (Zn) characterize the diets of under-nourished people. Zn deficiency is a global nutritional problem and intensity of the issue is even severe in developing countries. Cereal grains are key to fulfill a person’s daily energy requirements, but they have very low grain Zn concentrations, especially when grown in Zn-deficient soils. Zinc deficiency can be addressed in several ways viz., nutritional diversification, food enrichment and biofortification. Several limitations regarding nutritional diversification and food enrichment favored Zn biofortification as a perpetual solution of malnutrition. Among the potential biofortification options to rectify Zn deficiency, plant breeding approaches and agronomic biofortification offers major advantage. Current review appraised the possible role of Zn in plants, its uptake, translocation and partitioning efficiencies in cereal grains that is driven by various agronomic, breeding and biotechnological approaches. Moreover, review also discussed Zn application methods, Zn-phosphate hostility and indicators of Zn bioavailability which may improve Zn-use efficiency in rice. There is a genuine need to integrate Zn in rice production systems by using agronomic and conventional breeding tools. Likewise, agronomic biofortification is economically sustainable and practically adoptable solution to overcome the Zn deficiency issue in rice.     

Threats to fruit and vegetable crops: Fruit flies (Tephritidae) - ecology, behaviour, and management

Approximately 4,000 known/described species of fruit flies (Tephritidae) are distributed in tropical, subtropical, and temperate regions of world, out of which 200 species are economically important and damaging/spoiling not only to fruits but also to a number of vegetable crops. Despite their tremendous importance, a limited amount of information is available on the ecology and behaviour of fruit flies especially when compared to fruit fly species complex. It is necessary to understand the ecology and behaviour before the formulation of management strategy. The present review may serves as a baseline data for scientists engaged in fruit fly management programs. Key themes include: (1) demography and population dynamics and, (2) behaviour (e.g. sexual, mating, oviposition, and feeding). The excess of literature on monitoring and management of fruit flies are available, which includes male sterilization and annihilation, mass trapping, chemical baits, mating disruption, and biological control. But few of them are easily adopted by users and give satisfactory control of fruit flies and rest are not easily adopted or if used does not give effective control, because of the lack of knowledge about the ecology and behaviour of fruit flies. If the information on population dynamics, behavior, and the related ecological factors are not jointly gathered, it is almost impossible to carry out an appropriate pest control at the right time and place. We hope that this synthesis will lay the groundwork for future ecological and behavioural studies of fruit fly species, populations, communities, and control.     

New records of eriophyoid mites (Acari: Prostigmata: Eriophyoidea) from Saudi Arabia

A field study was conducted to investigate eriophyoid mites associated with some fruit trees in Riyadh, Saudi Arabia. The survey was carried out in four localities (El-Waseel, Al-Beer, Al-Haiyer and El-Deriya) and included seven species of fruit trees, namely olives (Olea europea), fig (Ficus carica), grapes (Vitis vinifera), apple (Malus domestica), citrus (Citrus spp.), pomegranate (Punica granatum) and pear (Pyrus communis). Seven new records of eriophyoid species (Aceria benghalensis Soliman and Abou-Awad, A. olivi Zaher and Abou-Awad, Caleptrimerus baileyi K., Colomerus oculivitis (Attiah), Oxycenus niloticus (Zaher and Abou-Awad), Rhynchaphytoptusficifolia (Keifer) and Tegolophus hassani (Keifer)), belonging two families, Eriophyidae and Diptilomiopidae, were collected from four species of fruit crops covering four different production localities in Riyadh. An illustrated identification key for these mites is provided. The present study is the first scientific study on Saudi eriophyoid mites.     

Time course of δ1¹³C in poplar wood: genotype ranking remains stable over the life cycle in plantations despite some differences between cellulose and bulk wood

Genetic differences in δ13C (isotopic composition of dry matter carbon) have been evidenced among poplar genotypes at juvenile stages. To check whether such differences were maintained with age in trees growing in plantations, we investigated the time course of δ13C as recorded in annual tree rings from different genotypes growing at three sites in southwestern France and felled at ～15-17 years. Wood cores were cut from tree discs to record the time course of annual basal area increment (BAI). The isotopic ratio δ13C was recorded in bulk wood and in extracted cellulose from the annual rings corresponding to the period 1996-2005. Discrimination against 13C between atmosphere and tissues (Δ13C) was computed by taking into account the inter-annual time course of δ13C in the atmosphere. Annual BAI increased steadily and stabilized at about 8 years. An offset in δ13C of ～1‰ was recorded between extracted cellulose and bulk wood. It was relatively stable among genotypes within sites but varied among sites and increased slightly with age. Site effects as well as genotype differences were detected in Δ13C recorded from the cellulose fraction. Absolute values as well as the genotype ranking of Δ13C remained stable with age in the three sites. Genotype means of Δ13C were not correlated to annual BAI. We conclude that genotypic differences of Δ13C occur in older poplar trees in plantations, and that the differences as well as the genotype ranking remain stable while trees age until harvest.     

Evaluation of F1 and BC1 hybrids of Lilium lancifolium × Asiatic hybrid ‘Chianti’ by morphological analysis and fluorescence in situ hybridization

Lilium lancifolium Thunb. exhibits wide genetic diversity and numerous genetic traits within progeny populations. Parent morphology affects the distribution and assortment of progeny phenotypes. In this study, morphological analysis and fluorescence in situ hybridization (FISH) were conducted for cross progeny (F1 and BC1). Results showed that F1-1 hybrids had greater plant height than the parents; however, backcross progeny plant height (group 1) was low. Leaf number in both groups was considerably low in F1 hybrid, although high in backcrossed plants. Flower number and days to flower opening were intermediate to those of the parents for F1 hybrids, yet low in BC1 progeny. In group 1, backcross progeny showed small bulb length; however, group 2 progeny showed large bulb length. Positive and negative correlations between the phenotypic traits of parents and progeny confirmed significant variations. According to FISH results, F1-1 and F1-2 hybrids distinctly exhibited nine and eight 45S rDNA loci which were same in position with 45S loci of the parents. In backcross progeny, eight 45S rDNA signals were detected in four BC1 progeny of group 1, while 10 signals were observed in all group 2 progeny, same with the L. lancifolium karyotype. Morphological analysis and FISH helped in scrutinising progeny to obtain hybrids with desirable characteristics.