Reconstructing an ancient bottleneck of the movement of the lentil (<Emphasis Type="Italic">Lens culinaris</Emphasis> ssp<Emphasis Type="Italic">. culinaris</Emphasis>) into South Asia

Crop movement often leads to genetic bottlenecks. The lentil was domesticated in the Eastern Mediterranean region. Dissemination from highland Afghanistan into the Indo-Gangetic Plain, where it is of major importance today, caused a founder effect creating a genetic bottleneck. To understand the process and assist breeders with broadening the consequent narrow genetic base, this study re-constructs the founder effect by a re-examination of historical world germplasm evaluations at an intermediate elevation site in Pakistan–Islamabad, and at a low elevation site—Faisalabad representative of the Indo-Gangetic Plain. At Islamabad 72% of landrace accessions of an Afghan origin did not flower and the remaining Afghan accessions were among the latest flowering accessions in the world germplasm collection. At Faisalabad late flowering accessions produced low yields with each week’s delay in flowering giving a yield loss of 9.2%. Prehistorically Afghan lentil germplasm probably harboured recessive alleles for time to flower, possibly from introgression with wild lentil (Lens culinaris ssp. orientalis) in Afghanistan, which were then cyclically recombined and selected for as part of the dissemination process into the Indo-Gangetic Plain.     

Growth stage-based response of wheat (Triticum aestivum L.) to kinetin under water-deficit environment: pigments and gas exchange attributes

Plant growth regulator, kinetin, is known to modulate the key physiological processes under abiotic stresses in different crops. However, kinetin-mediated response at different growth stages of crop plants is lagging behind. Therefore, a field experiment was conducted to appraise the potential role of exogenously applied kinetin in alleviating the effects of water scarcity on wheat. Three levels of kinetin (0, 75, and 150 mg/L) were used either as seed treatment or foliar spray at the vegetative or the post-anthesis stage. Water deficit markedly reduced shoot fresh mass, plant chlorophyll level, flag leaf photosynthesis, stomatal conductance, and transpiration rate. Degradation of chlorophyll a was greater in plants subjected to post-anthesis water-deficit conditions. However, plants growing under continuous water-deficit conditions had significantly lower concentration of chlorophyll b than those treated with water scarcity at the post-anthesis stage or receiving normal irrigation. Inhibited photosynthesis of wheat in response to post-anthesis water-deficit conditions was largely due to non-stomatal factors. In contrast, stomatal factors were the main constraints for photosynthesis in plants growing under continuous scarcity of water. Plants subjected to continuous water starvation had markedly lower grain yield than those subjected to water-deficit conditions at post-anthesis stage. Application of kinetin before seed sowing or at the post-anthesis stage significantly reduced the negative effects of drought on flag leaf chlorophyll and stomatal conductance. Lower level of kinetin (75 mg/L) was found to be more effective in mitigating the inhibitory effects of water shortage on photosynthesis and growth, and improved grain yield under water scarcity.     

INFLUENCE OF DIFFERENT RATES OF PHOSPHORUS ON GROWTH,YIELD AND PHOSPHORUS USE EFFICIENCY IN TWO WHEAT CULTIVARS

To study the influence of different rates of phosphorus (P) on growth and yield of wheat, experiments were conducted at NIAB, Faisalabad, Pakistan under natural conditions. Results indicated that the P requirement of wheat at early growth was higher and adequate available P in the growth medium helped to attain relatively higher growth rate and resulted in higher grain yield. The two wheat cultivars when subjected to different rates of P application showed that the cultivar ‘MH-97’ was more responsive than ‘Pasban-90’ that attributed to its higher P translocation efficiency from roots to tops. The two cultivars also showed differential yield response when grown under field condition. At optimum nitrogen (N): P ratio of 1.5:1, the cultivar ‘MH-97’ gave 31.5% while cultivar ‘Pasban-90’ gave a maximum response of 25.9% over their respective N alone application. Contrarily, at the wider NP ratio of 3:1, yield response of cultivar ‘MH-97’ was 26.5% while that of cultivar ‘Pasban-90’ was only to the extent of 2.2%, thereby indicating a much wider difference in their yield response pattern. Thus, choosing an appropriate cultivar for a particular rate of fertilizer application would be more rewarding in terms of yield and profitability.     

MINERAL COMPOSITION OF STRAWBERRY,MULBERRY AND CHERRY FRUITS AT DIFFERENT RIPENING STAGES AS ANALYZED BY INDUCTIVELY COUPLED PLASMA-OPTICAL EMISSION SPECTROSCOPY

Mineral contents of strawberry (Fragaria x ananassa), mulberry (Morus alba, M. nigra, M. macroura, and M. laevigata) and cherry (Prunus avium) fruits at un-ripened, semi-ripened and fully-ripened stages were investigated. The concentrations (mg kg^?1) of potassium (K), phosphorus (P), calcium (Ca), and magnesium (Mg) in the fruits (DW), at fully-ripened stage, varied from 2600 (mulberry) to 3300 (strawberry), 1854 (cherry) to 2954 (mulberry), 1855 (cherry) to 4375 (mulberry) and 1025 (cherry) to 2225 (mulberry), respectively. Sizeable amounts (mg kg^?1) of Zn 408 (strawberry) to 1110 (mulberry) and Fe 236 (cherry) to 1080 (mulberry) were also determined. Moreover, the tested fruits contained considerable amounts of sodium (Na), manganese (Mn), aluminum (Al), and copper (Cu). Overall, the concentrations of these minerals except K were found to decrease as fruit maturity progressed. The tested fruits, especially Morus species, can be explored as a rich source of Zn and Fe, the two essential elements that are in short supply in human diet.     

Choice of nitrogen fertilizer affects grain yield and agronomic nitrogen use efficiency of wheat cultivars

Abstract

Nitrogen use efficiency (NUE) is low in cereals especially in wheat. Different wheat cultivars may vary in NUE due to inherited biological nitrification inhibition (BNI) potential. In this study, three wheat cultivars (Punjab-2011, ARRI-2011 and Millat-2011) were fertilized at the rate of 140?kg ha^?1 with three N sources [nitrophos (NP), urea and calcium ammonium nitrate (CAN)]. The soil nitrate (NO₃^?)-N contents were significantly enhanced coupled with simultaneous decrease in ammonium (NH₄⁺)-N contents in the rhizosphere of cultivar Punjab-2011, fertilized with NP; however, cultivar Millat-2011 receiving urea behaved in contrast. Wheat cultivar Punjab-2011 fertilized with NP had the highest grain yield and agronomic NUE than other treatments due to significant increase in chlorophyl contents, allometric and yield parameters. The highest net benefit was recorded from the cultivar Punjab-2011 fertilized with CAN. In conclusion, use of NP in Punjab-2011 enhanced the grain yield and agronomic NUE.     

Assessment of variation in drought tolerance using some key physiological criteria in potential wheat (Triticum aestivum L.) cultivars of different geographic origins

The present experiment comprised seven wheat cultivars, two drought levels (0 and 17% PEG-8000) and four replicates. The seeds of six wheat cultivars (Al-lugaimi, Bonus, Kronos, Yecora-rojo, Irena and Sama) were supplied by the King Saud University, Riyaz, Saudi Arabia, whereas S-24 was obtained from the Department of Botany, University of Agriculture, Faisalabad. The seeds were allowed to germinate and grow for 20 days in medium having full-strength Hoagland's nutrient solution or Hoagland's solution with 17% PEG-8000. For the appraisal of drought tolerance, various physiological traits such as gas-exchange attributes (A, E, C_i, g_s , and A/E), leaf water relations (ψ_w, ψ_s and ψ_p) and the activities of key antioxidant enzymes (SOD, POD and CAT) were determined. On the basis of biomass and gas-exchange attributes (A, E, and g_s ), cultivars Al-lugaimi and Sama were found to be drought tolerant, cultivars Yecora-rojo and Irena moderately drought tolerant, and cultivars S-24, Bonus and Kronos drought sensitive. However, plant osmotic adjustment and the activities of potential antioxidant enzymes (SOD, POD and CAT) were not found to be associated with drought tolerance of the different wheat cultivars.     

Effects of the application of ‘cash’ on the growth,fruit yield,and nutrient status of tomato (Solanum lycopersicum L.) grown in reclaimed saline soil

Summary

The effects of ‘cash’ [a novel 2:5:1 (w/w/w) mixture of calcium sulphate, ground sunflower heads, and humic acid] as a soil amendment on the growth, fruit yield, and leaf nutrient status of tomato (Solanum lycopersicum L.) grown on reclaimed saline soil (EC = 9.4 dS m^–1) were investigated. A glasshouse experiment was performed in a completely randomised design with six treatments (0, 10, 20, 30, 40, or 50 g ‘cash’ kg^–1 soil) each with four replicates. The results indicated that ‘cash’ increased both the shoot dry weight (DW) plant^–1 and the root DW plant^–1, the free proline contents of leaves, and leaf chlorophyll contents. The use of ‘cash’ also increased the number of fruit plant^–1, fruit yield pot^–1, and fruit vitamin C contents, although total soluble solids (TSS) contents were not affected. The contents of nitrogen (N), potassium (K), and calcium (Ca), and the Ca:Na ratios of leaf tissues increased with all application rates of ‘cash’. Leaf phosphorus (P) contents showed no response to any applied level of ‘cash’. Leaf sodium (Na) contents declined gradually with an increase in the level of ‘cash’ applied to the soil. We concluded that ‘cash’ has a pronounced positive effect on the growth and fruit yield of tomato plants grown in reclaimed saline soil. ‘Cash’ therefore has the potential to be used as a soil amendment for vegetable crops such as tomato to overcome the adverse effects of salinity in newly-reclaimed soils.     

Meat and bone meal as a potential source of phosphorus in plant-protein-based diets for Nile tilapia (Oreochromis niloticus)

A growth trial was conducted to evaluate meat and bone meal (MBM) as a source of Phosphorus (P) for Nile tilapia fed with plant-based diets on growth, and the efficiency of P utilization. Four isonitrogenous and isoenergetic diets were formulated. A plant-based diet, deficient in P (0.45 % diet, no P added), was used as the basal diet. Three levels of MBM were substituted for cornstarch in the base diet to produce experimental diets containing MBM_0.56, MBM_0.67, or MBM_0.78% P. These diets were fed (to apparent satiation) to Nile tilapia (initial body weight = 1.53 ± 0.01 g) for eight weeks. Weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR, feed:gain), whole-body P concentration (WBPC), protein retention (PR), and retained phosphorus (RP) increased significantly (P ≤ 0.05), with the increasing dietary P levels coming from MBM. Diets containing MBM_0.78 produced significantly greater WG, SGR, WBPC, PR, and RP compared to other experimental diets (P ≤ 0.05). The linear regression analysis revealed a positive correlation between the WG, WBPC, RP, and dietary P levels coming from MBM of Nile tilapia. These results indicate that MBM has an additional value as a source of P and can serve as a potential source of supplemental P for Nile tilapia fed plant-protein-based diets.     

Biochemical and Ultrastructural Changes of Some Tomato Cultivars after Infestation with Aphis gossypii Glover (Hemiptera: Aphididae) at Qalyubiyah,Egypt

Tomato plants are severely infested with Aphis gossypii in all over the world. The present investigation aims at evaluating effects of tomato leaf biochemical components as well as leaflet surface physical features on the susceptibility of five tomato cultivars (Alissa, GS, Logan, Super Strain B and Andos). Results clearly indicated significant differences among the five tested tomato cultivars according to their susceptibility to A. gossypii infestation. In addition, the cultivars Logan and Andos are the most susceptible, while Super Strain B and Alissa cultivars showed moderate resistance. The GS cultivar, finally, was the most resistant one. Photosynthetic pigments, biochemical components and antioxidant defense enzymes activity were negatively affected by infestation. Moreover, the density and length of leaflet non-glandular trichomes negatively effect on the population density of A. gossypii, while this was not the case with glandular trichomes. From these results, the susceptibility of tomato cultivars on the basis of these results in the integrated aphids management programs.