Effect of Phosphorus Sources and Arbuscular Mycorrhizal Inoculation on Growth and Productivity of Snap Bean (<Emphasis Type="Italic">Phaseolus vulgaris</Emphasis> L.)

Phosphorus (P) is the second major plant nutrient required for plant growth. Different sources of water soluble P have been used to increase growth and yield of legumes. In addition, mycorrhizas have a potential role in increasing soil P supply. A factorial experiment was conducted to evaluate the effect of different phosphorus sources (monoammonium phosphate, monopotassium phosphate, urea phosphate, calcium superphosphate and phosphate rock fortified Bacillus megaterium) and arbuscular mycorrhizal inoculation (with or without) on growth and productivity of snap bean (Phaseolus vulgaris L.) cv. Paulista in plastic bags filled with sandy soil during 2014 and 2015 seasons at the Experimental Research Farm of the Horticulture Department, Faculty of Agriculture, Ain Shams University, Qalyubia Governorate, Egypt. The experiment was laid out in a completely randomized design with three replications. Results revealed that fertilization with monoammonium phosphate (MAP) significantly increased vegetative growth characteristics, yield, and total carbohydrates and protein content in green pods concomitantly with increases in chlorophyll and nutrients content in the leaves. Moreover, arbuscular-mycorrhizal inoculation significantly increased all above mentioned data compared with non-mycorrhizal inoculation. In addition, plants inoculated with arbuscular mycorrhizal and fertilized with MAP showed a synergistic effect.     

Effects of Irrigation Water Salinity and Water Depth On Growth and Yield Parameters of NERICA Rice (Oryza sativa L. × Oryza glaberrima L.)

NERICA rice was developed through the hybridization of Oryza Glaberrima and Oryza sativa in an attempt to produce a higher yield in areas with a limited water supply. This study investigated the interactive effects of irrigation water salinities (0.38, 1.5, 3.0, 5.0, 7.0, 10.0 and 15?dSm^?1) for various water depths (5, 10 and 15?cm) on crop yield and related components of NERICA rice variety. This study showed that increased levels of irrigation water salinity resulted in reduced rice yield, biomass weight, plant height, harvest index, 1000 grain weight, evapotranspiration, water use efficiency, stomatal conductance, and chlorophyll content, and increased plant sterility for all irrigation water depths. The threshold values of soil salinity for the NERICA rice for the 5, 10, and 15?cm depths were 2.14, 81 2.80, and 1.98 dSm^?1, respectively. The study showed that the optimum salinity/water depth condition for the production of transplanted NERICA rice is irrigation water salinity <?1.50 dSm^?1, and a 10?cm water depth. This irrigation water salinity level maintains the soil ECe at or below the salinity threshold value of 2.80 dSm^?1. This study showed that NERICA rice has a salinity threshold value of 2.80 dSm^?1. Since rice is generally considered to be more salt-sensitive during germination, it is recommended that farmers apply the least saline water available during the rice germination stage of growth. Information from this study will assist policymakers and farmers to better manage NERICA production in Sub-Saharan Africa.

     

The Effect of Growth Regulators and a Biostimulator on the Health Status,Yield and Yield Components of Potatoes (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.)

In this study, the influence of potato cultivars Irga, Satina, Valfi, Blaue St. Galler and Highland Burgundy Red (HB Red), growth regulators: Bio-Algeen S?90, Kelpak SL and Trifender WP, and the biostimulator Asahi SL on the health status of potato plants and tuber yield was investigated. The severity of late blight and early blight was estimated during the growing season. After harvest, potato tuber yield was determined according to size fractions. The applied treatments significantly reduced the severity of late blight in cv. Irga (Kelpak SL), Valfi (Bio-Algeen S-90, Kelpak SL, Trifender WP) and Blaue St. Galler (Trifender WP) in 2013. In 2015, the symptoms of early blight were significantly reduced in cv. Irga after the application of all tested bioregulators. HB Red was characterized by the best health status among the evaluated cultivars. Kelpak SL and Bio-Algeen S-90 increased the tuber yield of cvs. Irga and HB Red, respectively, in 2013, and Trifender WP increased the tuber yield of cv. Satina in 2014. In the first year of the study, the applied growth regulators and biostimulator significantly increased the percentage of medium-sized tubers of cv. Blaue St. Galler, and Bio-Algeen S-90 increased the percentage of medium-sized tubers of cv. HB Red.     

Effect of pre‐storage seed treatments on adult mortality,oviposition and development of Callosobruchus chinensis L. (Bruchidae: Coleoptera), and the viability of mungbean (Vigna radiata (L.) Wilczek) in India

Abstract

The adult mortality of Callosobruchus chinensis L. was 100% within 24 h after artificially infesting seeds pretreated with inert clay and stored for 12 months under ambient conditions. Pre‐treatment with thiram and delsan‐30 (TCMTB) were also effective in controlling the adults by impairing oviposition. The seeds maintained over 80% germination up to 12 months of storage under all the treatments.     

Effects of herbicides on rice resistance and on multiplication and feeding of brown planthopper (BPH), Nilaparvata lugens (StÅl) (Homoptera: Delphacidae)

Two-way effects of herbicide on rice resistance and multiplication and feeding of the rice brown planthopper (BPH), Nilaparvata lugens (Stål) were studied. Four of 11 herbicides tested, butachlor, metolachlor, oxadiazon and bentazone, had significantly stimulating effects on multiplication and feeding of BPH. Multiplication times (N ₁/N ₀) of BPH on the rice treated with the four herbicides were 674, 367, 322 and 311, respectively, while that of N. lugens on the untreated plants was 159. The results of measurements of honeydew production by BPH indicated that the feeding rates of the brown planthoppers increased when the insects fed on the plants treated with bentazone, quinclorac, oxadiazon and quinclorac. Survival rates of N. lugens first to third-instars rose on the rice plants treated with butachlor, bentazone, but that of the fourth and fifth instars were not affected. Furthermore, all of those herbicides tested led to a decline of rice resistance, i.e. the injury scales of the treated plants were larger than that of the control under the same pest stress. Based on their effects on rice resistance and on BPH, the herbicides tested can be divided into two categories, one affecting rice resistance and BPH multiplication, the other affecting rice resistance only.     

Effects of nC24 and nC27 petroleum spray oils on oviposition and egg survival of Ostrinia nubilalis Hübner (Lepidoptera,Pyralidae) and Trichogramma brassicae Bezdenko (Hymenoptera,Trichogrammatidae) adults on maize plants

Abstract

The study determined the effectiveness of nC24 and nC27 petroleum spray oils (PSOs) to reduce oviposition of Ostrinia nubilalis and survival of O. nubilalis eggs and Trichogramma brassicae adults. Under choice and no-choice tests, maize treated with 3, 5 and 10% (v/v) of both oils deter O. nubilalis oviposition on maize. The study also showed that treatment of 1 – 3-day-old O. nubilalis eggs with 1 and 2% (v/v) nC24 oil caused 6% mortality compared with 99.5% when treated with 3, 5 and 10% (v/v) oil. In contrast, treatment with 1 – 10% (v/v) nC27 oil caused 99% mortality. Trichogramma brassicae is a major parasitoid of O. nubilalis. The mortality of T. brassicae 24 h after exposure to maize sprayed with 2% (v/v) nC24 and nC27 oils was 8.3 and 12.7%, respectively. At 5% (v/v), the mortalities were 24.9 and 23.5%, respectively. Therefore, application of 3% (v/v) PSO may deter O. nubilalis egg lay, egg mortality and survival of T. brassicae on maize.     

Effects of short-term low temperatures on photosystem Ⅱ function of samara and leaf of Siberian maple (Acer ginnala) and subsequent recovery

Samara is the reproductive organ (seed) for many tree species in arid land in northwestern China. It is ecologically important in population development due to its dispersal function. However, information on its photosynthesis and effect of environmental stresses on its photosynthesis is still very limited. In the present study, responses of photosystem II (PSII) activity in samara and leaf of Siberian maple to short-term chilling/freezing and subsequent recovery potential were comparatively investigated by using polyphasic fluorescence test. The samara had more efficient photosynthesis (Fv/Fm and PIABS) and more efficient electron transport (φEo) but lower energy dissipation (DIo/RC) than leaf. Generally, the PSII performance and the electron transport for both samara and leaf were inhibited under low temperature stress, accompanied by an increase of energy dissipation in PSII reaction centers (RCs). PSII of both samara and leaf was not markedly affected by chilling and could acclimate to chilling stress. Short-term freezing could completely inhibit PSII activity in both samara and leaf, indicated by the drop of values of Fv/Fm, PIABS, φEo to zero. PSII functional parameters of short-term dark frozen samara could be largely recovered whereas those of frozen leaf could not be recovered. The higher tolerance of samara to short-term low temperature stress than leaf is of great ecological significance for seed development, population establishment of Siberian maple.     

Effect of Cotton leaf curl virus infected plants on the biology of the whitefly,Bemisia tabaci (Hemiptera: Aleyrodidae): Vector–virus mutualism

Cotton leaf curl virus (CLCuV) (Geminiviridae : Begomovirus), the causative agent of leaf curl disease in cotton plants (Gossypium hirsutum), is exclusively transmitted by whitefly species Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). CLCuV transmission occurs in Sriganganagar (Rajasthan), an area endemic with cotton leaf curl disease. The relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. To further understand these relationships, fecundity and life history parameters of an indigenous non- b (Asia II genetic group) biotype whitefly, B. tabaci, were compared on 10, 25, and 40 days post-inoculation (DPI), in CLCuV-infected and healthy cotton plants to determine the effect of virus on its vector. The development time of the immature stages of whiteflies was significantly reduced on CLCuV-infected plants. The development time of the immature stages did not change with severity of symptoms at 25 and 40 DPI (45- and 60-d-old plants). Cotton leaf curl virus infection increased percent egg viability of B. tabaci. Whiteflies deposited significantly fewer eggs on virus-infected plants than on healthy plants. Whiteflies had better egg viability on younger plants than older plants, whereas plant age did not affect the fecundity. Male and female whiteflies had shorter longevity on CLCuV-infected plants than on healthy plants.     

Effects of sublethal concentrations of deltamethrin on fitness of white-backed planthopper,Sogatella furcifera (Horváth)

Sogatella furcifera (Horváth) is one of the most important migratory pests of rice in Asia. When normal concentrations of deltamethrin are applied to control lepidopteran pests of rice in the field, it is likely that S. furcifera will be exposed to sublethal concentrations of this chemical. Therefore, we examined the sublethal effects of deltamethrin on the development and reproduction of S. furcifera using the rice stem dipping method. The results showed that exposure of 3rd instar S. furcifera to LC₁₀ and LC₂₅ deltamethrin significantly increased the emergence rates compared with the F₀ generation control group, but there was no significant difference in the nymphal stage duration, adult longevity and female fecundity. Nymphal duration of the F₁ generation was significantly prolonged under both treatments. Female fecundity also increased in this generation, with a significant difference between the LC₂₅ treatment group and controls. The relative fitness of the LC₁₀ and LC₂₅ treatment groups was 0.84 and 0.80, respectively. The results showed that sublethal concentrations of deltamethrin stimulate the reproduction of S. furcifera, but decrease the relative fitness of the population. These results provided a reference point for the application of insecticides to control S. furcifera.     

Effects of Cry1Ac toxin of Bacillus thuringiensis and nuclear polyhedrosis virus of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on larval mortality and pupation

In the laboratory, the percentage mortality and pupation of Helicoverpa armigera (Hübner) were investigated when larvae were exposed to Cry1Ac of Bacillus thuringiensis Berliner, nuclear polyhedrosis virus of H. armigera (HaNPV) or Cry1Ac and HaNPV together. The results revealed that interactions between Cry1Ac and HaNPV varied with bioassay method and concentration of the suspension. When larvae were infected using a suspension containing both HaNPV and Cry1Ac, most combinations of Cry1Ac (62.5, 125 and 250 microg mL(-1)) and HaNPV (1.2 x 10(6), 6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae were force fed diet containing Cry1Ac 48 h after being infected by HaNPV, interaction between Cry1Ac (0.5, 1, 2, 4 and 8 microg mL(-1)) and HaNPV (6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an additive effect, while combinations of Cry1Ac (0.5, 1, 2 and 4 microg mL(-1)) and HaNPV (1.2 x 10(6) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae being infected by HaNPV were fed on Cry1Ac diet from neonate to death or pupation, the results suggested that Cry1Ac and HaNPV showed an additive interaction. The percentage mortality was lower in the treatment of larvae infected by transgenic Bt cotton leaf discs containing HaNPV suspension than in the treatment of larvae by conventional cotton leaf discs containing HaNPV, while the pupation rate was higher. The combination of Bt cotton and HaNPV showed antagonism. The present results showed that a combination of Cry1Ac and HaNPV usually resulted in mortality levels greater than in the case of Cry1Ac but not greater than with the virus alone.     

Studies on the biology of Cryphalus piceae (Ratz.) (Coleoptera, Scolytidae) in the Bartin and Karabük regions of Turkey

The purpose of this study is to investigate the biology of Cryphalus piceae (Ratz.) (Col., Scolytidae) living in Abies bornmülleriana (Mattf.) in fir forests in the Western Black Sea region in Turkey. The dates of swarming, tree attack, egg-laying, and different stages of development are given. The species had two generations per year.     

Effect of the disodium salt of cyclopentene β,β′-triketone on the development of infections induced by TMV in the leaves of hypersensitive and susceptible tobacco plants

Journal of Plant Diseases and Protection - We show here that the disodium salt of 2-acetyl-5-chloro-4- hydroxycarbonylmethylthiocyclopent-4-ene-1,3-dione (salt 2) inhibits tobacco mosaic virus...     

Dissipation of quinalphos (O,O, diethyl O‐quinaxalin‐2yl phosphorothioate) residues in and/or on cauliflower (Brassica oleracea Var. Botrytis)

Abstract

A field trial was conducted to study the magnitude of quinalphos residues in and/or cauliflower (Brassica oleracea Var Botrytis. The cauliflower crop was sprayed once with quinalphos 25 e.c. at 0.25 and 0.5 kg a.i./ha 104 days after transplanting. The samples of cauliflower drawn at different time intervals were analysed colorimetrically. The initial deposits of quinalphos on cauliflower were found to be 5.79 and 9.52 ppm, an the half life values 1.61 and 2.12 days, respectively, at 0.25 and 0.5 kg a.i./ha. The waiting periods determined were 11 days at the higher and 7 days at the lower dose of quinalphos.     

Effectiveness of two insect growth regulators against Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) and their impact on population densities of arthropod predators in cotton in Pakistan

Field efficacies of two insect growth regulators (IGRs) at two recommended application rates, buprofezin at 370 and 555 g AI ha(-1) and lufenuron at 37 and 49 g AI ha(-1), were determined against the sweet potato whitefly, Bemisia tabaci (Gennadius), and the cotton bollworm, Helicoverpa armigera (Hübner), in experimental plots of cotton at the Directorate of Cotton Research, Faisalabad, Pakistan. Adverse effects of the IGRs on populations of associated arthropod predators, namely geocorids, chrysopids, coccinellids, formicids and arachnids, were also assessed. Both IGRs significantly reduced populations of B. tabaci at each application rate 24, 48 and 72 h after treatment, and higher doses were more effective than lower doses. Buprofezin was not effective against H. armigera at any tested dose for any time of treatment in any spray. Lufenuron applied at 37 and 49 g AI ha(-1) effectively suppressed H. armigera populations, resulting in significant reductions in crop damage. At lower doses, both IGRs appeared safe to predator populations, which did not differ significantly in IGR-treated versus untreated control plots. Population densities of formicids and coccinellids were significantly lower at high concentrations of both IGRs in treatment plots, possibly as a result of reduced prey availability. The potential role of buprofezin and lufenuron for control of B. tabaci and H. armigera in a spray programme and the likelihood of direct toxic effects of IGRs on predatory fauna of cotton are discussed.     

Males of Ichthyofilaria argentinensis Incorvaia, 1999 and I. bergensis (Wülker, 1930) (Dracunculoidea:Guyanemidae): new morphological aspects and emendation of the generic diagnosis

Abstract: The adult male of dracunculoid nematode Ichthyofilaria argentinensis Incorvaia, 1999 (Guyanemidae) is described for the first time based on specimens found in the swimbladder of its type host, Merluccius hubbsi Marini (Merlucciidae), caught off the coast of Buenos Aires, Argentina (western Atlantic Ocean). In addition, the males of Ichthyofilaria bergensis (Wülker, 1930) K?ie, 1993 are redescribed from specimens collected from the body cavity and visceral surface of Molva macrophthalma (Rafinesque) (Lotidae) caught in the western Mediterranean Sea, off the coast of Sardinia. Light and scanning electron microscopy examinations revealed some new morphological features for the genus, such as a pair of deirids located near the end of muscular oesophagus, the body wall conspicuously twisted immediately anterior to the cloaca, the presence of a copulatory plate, one pair of adcloacal papillae and a pair of phasmids situated on the posterior half of the tail. On the basis of this material, the generic diagnosis of Ichthyofilaria is modified to include some of these newly observed features, as well as to indicate the absence of spicules. The diagnosis of Guyanemidae is extended to include that a copulatory plate and/or two spicules may be present as characteristics for this family.     

Efficacy of mating disruption technique against carob moth,Apomyelois ceratoniae Zeller (Lepidoptera: Pyralidae) in pomegranate orchards in Southeast Turkey (Şanlıurfa)

Carob moth, Apomyelois (=Ectomyelois) ceratoniae Zeller (Lepidoptera: Pyralidae) is a key pest in pomegranate orchards in Southeast of Turkey. The pest causes significant damage and reduces marketability of fruits, and is difficult to control with insecticides. Therefore, it is imperative to develop environmentally sound effective alternative management approaches. In this study, we aimed to evaluate the mating disruption technique and determine the appropriate application dose for the management of the pest. The study was carried out in Central and Suruç districts of ?anl?urfa province (Turkey) in 2011 and 2012. SPLAT EC (Specialized Pheromone-Lure Application Technology) trade named dispenser containing 2% Z7, E9-11-dodecatrienyl formate pheromone mimic was applied at 500, 625 and 750 g/ha in three pomegranate orchards in each district. Results indicated that mating disruption technique significantly reduced the pest populations. But effectiveness of the method was less in terms of the damage rate on fruits. Pheromone applied at 500 g/ha was not effective. However, application at 625 g/ha reduced the pest populations to an acceptable level. Thus, the concentration could be considered an appropriate dose for the less abundant pest population within integrated pest management while higher population would require combining the mating disruption method with a bio-insecticide.     

Two-year Investigations on Herbicide-Resistant Silky Bent Grass (Apera spica-venti L. Beauv.) Populations in Winter Wheat��Population Dynamics, Yield Losses, Control Efficacy and Introgression into Sensitive Population

In this study, the results of two-year investigations on herbicide resistance in silky bent grass (Apera spica-venti) populations are presented. Two populations of A. spica-venti were sown in a winter wheat field at the Ihinger Hof Research Station near Stuttgart in Germany in October 2008. Whole-plant bioassays conducted with both populations in the greenhouse before the field trial was set up revealed that population A was strongly resistant to acetolactate synthase (ALS)-inhibitors, whereas population B was sensitive to this group of herbicides. Each block was treated with isoproturon, fenoxaprop-P-ethyl, sulfosulfuron and meso-iodosulfuron at the recommended field dose. One treatment remained unsprayed. It was found that the average number of silky bent grass panicles was significantly higher in the second year (2010) with 343 panicles m^{? 2} in the untreated control compared to 44 panicles m^{? 2} in the first year (2009). Efficacy of both ALS-inhibitors was significantly reduced in the resistant population compared to the sensitive population. Grass-weed plants surviving treatments with ALS-inhibitors produced the same number of seeds as the untreated plants. It was found that germination rate of seeds from the resistant population was more than threefold higher than from the sensitive population. Grain yield was equal in all treatments and populations in 2009. In 2010, applications of isoproturon and fenoxaprop-P-ethyl resulted in higher grain yields, with a mean of 4.6 t ha^{? 1} compared to an average of 3.9 t ha^{? 1} in the plots treated with sulfosulfuron and meso-iodosulfuron and 4.3 t ha^{? 1} in the untreated plots. However, these differences were not statistically significant. The sensitive population of the second generation (2009/2010) was approximately 20% more tolerant to ALS-inhibitors than the sensitive population of the first generation (2008/2009) which indicates introgression of herbicide resistance traits already after one year. These results clearly show that herbicide resistance to ALS-inhibitors in silky bent grass is likely to spread rapidly causing significant economic losses. Therefore, management strategies need to be developed and tested to prevent and overcome herbicide resistance in European cereal production systems.     

Gamma radiation sensitivity of the eggs, larvae and pupae of Indian meal moth Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae)

BACKGROUND: This study focused on determining the minimal effective gamma radiation dose that prevents commodity damage caused by the Indian meal moth Plodia interpunctella (Hübner). The study was also designed to assess the effect of releasing either partially sterilized males alone or both partially sterilized males and females on the reproductive potential of P. interpunctella populations. RESULTS: The dose of radiation required to prevent larval emergence from irradiated eggs was 350 Gy, and the same dose was also required to prevent adult emergence from mature larvae. A dose of 300 Gy was not able to prevent adult emergence from irradiated pupae. The dose at which 100% sterility was achieved in treated females mated to treated males was 300 Gy for the parental generation of irradiated pupae. Fertility of the parental males from irradiated pupae was 48.17% at 300 Gy in treated males crossed with untreated females, but male progeny of irradiated male parents had a residual fertility of 11.06% at the same dose. CONCLUSION: F(1) males from irradiated pupae were more sterile than parental males. To prevent larval emergence from irradiated eggs, a dose of 350 Gy is required. The same dose is required to prevent the larvae from reaching the adult stage.