Response of Rice Seedlings to Copper Toxicity and Acidity

Metal toxicity and soil acidity affect plant growth. A hydroponic experiment was conducted to simulate effects of pH and copper concentration [Cu] on early growth and biomass production of high-yielding rice seedlings (Oryza sativa L. cv. ‘NIAB 6’). The rice seedlings were allowed to grow in Yoshida nutrient solution with 1 (control), 8, 16, and 32 μM Cu at buffered pH levels of 4.5, 5.0, and 5.5, respectively. Shoot and root growth, leaf chlorophyll content, and root lipid peroxidation and K⁺ leakage of 15-day-old rice seedlings were determined. Results show that [Cu] had significant adverse effects on rice seedlings. Shoot height and root length were reduced by 18%–60% and 7%–69%, respectively, compared with the control, and shoot and root weight decreased by 26%–56%, and 25%, respectively, in response to progressive increases in [Cu]. Similarly, leaf chlorophyll content decreased by 150%–245% compared with the control treatment. Rice seedling roots suffered from significant increases in lipid peroxidation followed by K⁺ leakage (> 8–23 times) in response to increasing [Cu]. Averaged across [Cu], seedling growth and biomass were greater at pH 5.5 than at other pH treatments. In some instances, increasing pH minimized the adverse effects of Cu at low concentrations on rice seedlings.     

Simultaneous use of plant growth promoting rhizobacterium and nitrogenous fertilizers may help in promoting growth,yield, and nutritional quality of okra

This study was conducted to evaluate the simultaneous use of plant growth promoting rhizobacterium (QS1) and different combinations of urea-nitrogen and biogas slurry-nitrogen for improving growth, yield, and nutritional quality of field grown okra. The isolate QS1 was identified as Bacillus sp. QS1 based on its ribosomal ribonucleic acid (rRNA) sequence analysis. Results revealed that among the combinations, the application of 50% urea-nitrogen + 50% biogas slurry-nitrogen was optimal for improving crop performance. This combination significantly (p ≤ 0.05) promoted okra growth viz. plant height (69.63–80.03 cm), no of branches per plant (14–18), shoot fresh weight (86.66–136.25 g/plant), root fresh weight (22.5–26.58 g/plant), and fruit yield (8.5–13.5 kg/plot) compared to the plants receiving 100% urea-nitrogen. The interactive effective of this nitrogen combination and QS1 inoculation produced the highest growth and yield response. Similarly, the same treatment improved nitrogen, phosphorus, potassium, and protein contents in shoot and fruit of okra compared to other treatments.     

Farmer’s Perception of and Factors Influencing Agroforestry Practices in the Indus River Basin,Pakistan

Agroforestry practices of farming communities are investigated in southern Punjab province, Pakistan. It is hypothesized that rural people of this areas are more inclined than elsewhere in the province to practice agroforestry due to greater profitability than cropping. A landholder survey revealed that the majority of farmers are inclined to plant trees on their land. Low accessibility of institutional credit is a constraint for both agroforestry farmers (AF) and non-agroforestry farmers. However, among AF respondents only 24% were found to need credit for agroforestry practice, as against nearly 76% for crop production. Mostly farmers were found to have positive perceptions regarding agroforestry practice, because they understand the multiple benefits from growing trees, compared with cropping where farmers face various constraints, including poor access to credit, natural hazards, and little support from local authorities. Further, effort to sensitize farmers that growing trees has multiple benefits compared to only cultivation of field crops can bring about change in farmer’s perceptions and attitudes in the Indus River basin, resulting in motivation for agroforestry adoption.     

Age-related declines in ejaculate quality and sperm kinematics vary among strains of Japanese Quail (Coturnix japonica)

For successful breeding programs, it is important to quantify the useful period of a male's reproductive life and it is often done simply by measurement of semen quality. This information is lacking for Japanese quail so we tested whether there is a decline in ejaculate quality and sperm kinematics with age, and whether the decline varies among strains. Nine males (n = 9) from each of 5 strains (A, B, C, D and E) were subjected to 4 semen collections (n = 16 per male) at 8, 16, 26 and 36 weeks of age. Ejaculate volume, sperm concentration and total sperm per ejaculate were measured, and sperm kinematics were analysed using a Sperm Class Analyser (SCA^®). There was a significant effect of age for ejaculate volume, total sperm per ejaculate and per cent medium sperm. The effect of the interaction between age and strain was significant for percent progressive motile sperm, percent rapid sperm, velocity curvilinear, velocity straight line, velocity average path, linearity, straightness and beat cross frequency. Ejaculate volume peaked at Week 26 in all strains, while peak values for sperm concentration and total sperm per ejaculate were observed at Week 16 for most strains. There were declines in percent motile sperm, progressive motile sperm and rapid sperm, and in velocity curvilinear velocity, velocity straight line and velocity average path, by Week 16 for most strains. Linearity declined by Week 26 in some strains, and all strains showed a significant decline in beat cross frequency by that age. In conclusion, the ability of CASA to detect age-related changes in sperm kinematics makes it a valuable tool for identifying the best males and thus improving quail flock fertility. It is essential that breeders understand that age affects both sperm production and sperm kinematics, and that the changes vary with strain.     

Optimization of Agrobacterium-mediated transformation parameters for Melastomataceae spp. using green fluorescent protein (GFP) as a reporter

Agrobacterium-mediated transformation for both Melastoma malabathricum and Tibouchina semidecandra were optimized using green fluorescent protein (GFP) as a reporter. The binary vector pCAMBIA1304 harboring the modified green fluorescent protein (mgfp) gene driven by the CaMV 35S promoter was used. Parameters optimized were bacterial strain, bacterial concentration, pre-culture period, co-cultivation period, immersion time, acetosyringone concentration and wounding type. Results obtained were based on the percentage of GFP expression which was observed 3 days post-transformation. Agrobacterium tumefaciens strain LBA4404 and EHA105 at concentration 1 × 10⁷ cfu ml⁻¹ (OD_600nm 0.8) showed the highest virulence on M. malabathricum and T. semidecandra, respectively. Four days of pre-culture and 2 days of co-cultivation were optimum for M. malabathricum transformation, while 3 days of pre-culture and co-cultivation for T. semidecandra. Result also showed that 60 min of immersion and addition of 200 μM acetosyringone gave the highest percentage of positive transformants for both M. malabathricum and T. semidecandra. Mild wounding also significantly increased the efficiency of M. malabathricum transformation.     

Alternate Two Different Modes of Actions of Green Chemicals to Combat Batrachedra amydraula Meyrick and Cadra cautella Walk on Date Palm Fruit,Egypt

Alternate two different modes of actions of green chemicals： spinosad ＆ methoxyfenozide to combat the lesser date moth, Batrachedra amydraula and the Almond moth, Cadra cautella Walk on dates in Dakhla Oasis, New Valley, Egypt were done in 2010 and 201 I. Based on infestation of the early insect pest B. amydraula, the three-rotation program with basic 1st spray of spinosad 24 SC at 20 mL/100 L showed insignificant difference. Based on minimum effective rotation doses, alternating spinosad 24 SC at 20 mL/100 L, then methoxyfenozide 24 SC at 15 mL/100 L with two-week interval showed zero infestation and 1.8% at the last sample of 2010 and 2011, respectively. Based on infestation of the late insect pest, Cadra spp., tlhe same previous trend of the three-rotation results. Based on minimum effective rotation doses, alternating spinosad 24 SC at 20 mL/100 L, then methoxyfenozid 24 SC at 15 mL/100 L with three-week interval indicated less than 1% and 1% infestation during harvest for 2010 and 201 l, respectively. The last reflected important value when storing the fruit. Both products proved to be working under dry hot high temperatures.     

Effect of 2‐hydroxy‐4‐(methylthio) butanoic acid and acidifier on the performance,chyme pH,and microbiota of broilers

This study was aimed to explore the comparative acidifying properties of 2‐hydroxy‐4‐(methylthio) butanoic acid (HMTBA) and a combination of DL‐methionine (DLM) and acidifier in male broiler production. A total of 480 1‐day‐old broiler chicks were randomly divided into four treatments: A (low HMTBA, 0.057% HMTBA); B (low acidifier, 0.05% DLM + 0.057% acidifier); C (high HMTBA, 0.284% HMTBA); and D (high acidifier, 0.25% DLM + 0.284% acidifier). At 21 d, growth performance, chyme pH, digestive enzyme activities, and intestinal microflora were measured. The pH of crop, gizzard, and ileum contents was higher in the HMTBA treatment group than in DLM + acidifier treatment group. Furthermore, acidifier supplementation promoted growth of butyrate‐producing bacteria such as Faecalibacterium, whereas high HMTBA (0.284%) inhibited the proliferation of acid‐producing bacteria including Roseburia and Collinsella. The chymotrypsin activity was lower in the HMTBA group than in the DLM + acidifier group. In contrast, high‐level HMTBA group showed higher average daily gain and average daily feed intake than the DLM + acidifier group. These results suggested that HMTBA work through different pathways with DLM plus acidifier.     

Denitrification losses from an irrigated sandy-clay loam under a wheat-maize cropping system receiving different fertilizer treatments

Studies were conducted on denitrification in the plough layer of an irrigated sandy-clay loam under a wheat-maize cropping system receiving different fertilizer treatments. The treatments were: N-100 (urea-N at 100kgha^–1year^–1), N-200 (urea-N at 200kgha^–1year^–1), FYM-16 (farmyard manure at 16 tonnes ha^–1year^–1), FYM-32 (farmyard manure at 32 tonnesha^–1year^–1) and the control (unfertilized). Averaged across sampling dates during the wheat season, the denitrification rate as measured by the C₂H₂-inhibition/soil-core incubation method was highest in N-200 (83gNha^–1day^–1), followed by FYM-32 (60gNha^–1day^–1, N-100 (51gNha^–1day^–1), FYM-16 (47gNha^–1day^–1) and the control (33gNha^–1 day^–1). During the maize growing season, average denitrification rate was highest in FYM-32 (525gNha^–1day^–1), followed by FYM-16 (408gNha^–1day^–1), N-200 (372gNha^–1day^–1, N-100 (262gNha^–1day^–1) and the control (203gNha^–1day^–1). Denitrification loss integrated over the whole vegetation period was at a maximum under FYM-32 (13.9kgNha^–1), followed by N-200 (11.8kgNha^–1), FYM-16 (10.6kgNha^–1) and N-100 (8.0kgNha^–1), whereas the minimum was observed for the control (5.8kgNha^–1). Under both crops, denitrification was significantly correlated with water-filled pore space and soil NO₃ ^–-N. The best multiple regression models accounted for 52% and 70% of the variability in denitrification under wheat and maize, respectively. Results indicated that denitrification is not an important N loss mechanism in this well-drained, irrigated sandy-clay loam under a wheat-maize cropping system receiving fertilizer inputs in the range of 100–200kgNha^–1year^–1. Received: 14 January 1997