Estimation of economic threshold level of alligator weed (Alternanthera philoxeroides (Mart.) Griseb.) to Tackle Grain quality and yield Losses in Rice

Alligator weed (Alternanthera philoxeroides) is the most troublesome invasive weed in transplanted rice ecosystems worldwide. A two-year field study was conducted to estimate economic threshold levels and the season long competitive effect of six alligator weed densities (0, 2, 4, 8, 16, and 32 plants m^?2) on yield and quality traits of transplanted rice. A gradual linear incline in dry weight of alligator weed was observed with an increase in its density from 2 to 32 plants m^?2. Maximum N (15.93–18.26 kg ha^?1), P (15.10–16.46 kg ha^?1) and K (16.34–17.81 kg ha^?1) uptake by alligator weed was recorded at its density of 32 plants m^?2. More micronutrient loss to the tune of 6.53, 47.92, 19.99, and 38.42 mg kg^?1 for Cu, Fe, Zn, and Mn, respectively was observed at the same density. Increasing density of alligator weed caused more losses in paddy yield (up to 21.37–23.78%), amylose and rice grain protein contents. According to a nonlinear hyperbolic regression model, maximum paddy yield loss of rice at asymptotic value of alligator weed density was 38.8% during 2011 and 42.4% during 2012. Economic threshold value of alligator weed was estimated 1.5 and 1.3 plants per m² during 2011 and 2012, respectively.     

Evaluation of sunflower (Helianthus annuus L.) single cross hybrids under heat stress condition

Sunflower is an important oilseed crop, which shows susceptibility to heat stress. In this study, 63 single cross hybrids were evaluated under heat stress condition for 2 years and compared with the two commercial hybrids. Genotype and genotype × environment (GGE) was used to differentiate single cross hybrids on the basis of multiple traits. GGE biplot showed that several single cross hybrids had higher seed yield potential than standard check. Moreover, seed yield per plant (SYP) was related to pollen viability percentage, showing that achene yield was the product of high gametophytic fertility under heat stress. Hybrids having high seed yield potential under heat stress had lower cell membrane injury. GGE biplot for SYP and its components showed that single cross hybrids were characterized into two major groups. Group I was further characterized into two sub group. Group Ia included hybrids with high 100-SW, while group Ib had the hybrids with high number of seeds per head and head diameter. Group II had the hybrids with high kernel weight and kernel to seed ratio. The hybrids could be recommended according to their potential utilization in the seed industry.     

Evaluation and management of acetyl-CoA carboxylase inhibitor resistant littleseed canarygrass (Phalaris minor) in Pakistan

A field survey was conducted for the sampling of Acetyl-CoA carboxylase (ACCase) inhibitor resistance littleseed canarygrass, a major weed of wheat, from Punjab, Pakistan in 2014 for confirmation of resistance. The surveyed regions encompassed four different cropping systems including rice–wheat, maize–wheat, cotton–wheat and mixed cropping. Dose–response assay was conducted for confirmation of resistance. Efficacy of herbicide mixtures including clodinafop–propargyl, metribuzin, pinoxaden and sulfosulfuron at a range of doses was investigated to manage littleseed canarygrass. Results revealed that all populations were resistant to fenoxaprop except PM-BWL-2. The higher level resistance (6.5) was found in populations collected from rice–wheat cropping system. The tested herbicide mixtures at 75% and 100% of the recommended dose of each mixture component provided the effective control of resistant littleseed canarygrass. Mixtures at 50% provided more than 80% control and reduced growth and seed production potential of surviving plants. The confirmation of ACCase inhibitor resistance as the first case of herbicide resistance in Pakistan, leads us to discourage use of ACCase inhibitor herbicides alone. However, herbicide mixtures at 75% and 100% of the recommended dose are suggested to manage this weed for sustainable wheat production in the surveyed cropping systems.     

Root zone selenium reduces cadmium toxicity by modulating tissue-specific growth and metabolism in maize (Zea mays L.)

The effects of selenium (Se) cadmium (Cd) interactions on plant growth and metabolism are not fully clear. In the present study, we assessed whether Se could alleviate the toxic effects of Cd on growth and metabolism of maize. Seeds of maize variety FH-985 were sown in pots filled with sand treated with CdCl₂ (0, 50 and 100 µM) and Se (0, 2 and 4 mg L^?1) through Hoagland’s nutrient solution. Low Se (2 mg L^?1) increased germination percentage and rate, while high Se (4 mg L^?1) increased fresh and dry biomass under Cd stress. Interestingly, all Se concentrations were effective in alleviating the toxic effects of Cd on photosynthetic pigments, whereas higher Se mitigated the Cd-induced oxidative stress and increased flavonoids both in the shoots and roots while phenolics in the roots. The results demonstrated that root zone Se altered tissue-specific primary metabolism in maize. Furthermore, low Se mitigated the Cd-induced decrease in total proteins in the root. Overall, Se-mediated decrease in the oxidative stress in the shoots while increase of secondary metabolites in the roots helped the plants to grow faster at early growth stage and caused increase in the biomass under different Cd regimes.     

Evaluation of foot and mouth vaccination for yak (<Emphasis Type="Italic">Bos grunniens</Emphasis>) in Pakistan

In northern Pakistan, many farming communities rely on domestic yak (Bos grunniens) as a principle source of income. A 2006 participatory disease surveillance report from this region indicated that foot-and-mouth disease (FMD) is the most prevalent annual disease of yak. Our objectives of this study were to determine exposure levels of yak to FMD virus; implement a vaccination program based on current, regional FMD virus serotypes and subtypes; and quantify immune responses following vaccination. Blood samples were used to determine pre-vaccination exposure of animals to FMD virus by antibody presence to non-structural proteins of FMD virus using a 3-ABC trapping indirect ELISA. Vaccine used consisted of FMD serotypes ‘O’ (PanAsia-2), ‘A’ (Iran-05), and ‘Asia-1’ (Shamir), but changed later during the study to match newly circulating viruses in the country (‘O’-PanAsia-2; ‘A’-Turk-06 and Asia-1-Sindh-08). Three hundred sixty-three blood samples were tested from selected villages to determine pre-vaccination FMD virus exposure in yak with an average of 37.7%. Immune responses from initial vaccination and booster dose 30 days later showed clear protective levels (as mean percent inhibition) of antibodies against structural proteins of serotypes ‘O,’ ‘A,’ and ‘Asia-1.’ These responses remained above threshold positive level even at day 210 following initial vaccination. Results of sero-surveillance and anecdotal information of repeated FMD outbreaks demonstrate the persistence of FMD virus of yak in northern Pakistan. Laboratory results and field observations clearly indicated that yak can be protected against FMD with a good quality vaccine with FMD serotype(s) matching current, regionally circulating FMD virus.     

Weed Control

Abstract

Research into weed control in Iraq is largely the responsibility of the Ministry of Agriculture. The recommendations which the Department of Weed Control have made on the basis of this research are presented. The principal weed species of Iraq are listed with some indication of their occurrence and importance. Both research and control of weeds in Iraq are limited at present.     

Effect of high temperatures on survival and longevity of the predator Cryptolaemus montrouzieri Mulsant

The effect of high temperature on survival and longevity of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) female adults was studied in the laboratory by daily exposure of the beetles to 35°C (mean r.h. 52%) combined with 1-, 2- and 3-h intervals of thermal treatment at 38, 40, 42 and 44°C (r.h. 46–48%). Fifty percent of females survived until the 12th–13th day of the thermal treatment at 38°C (depending on the exposure time), the 2nd–10th day at 40°C for 1–2 h exposure and the 4th–5th day at 42°C for 1 h exposure. Survival was 25–38% on the 1st–2nd day of the thermal treatment at 40, 42 and 44°C for 3, 2 and 1 h of exposure, respectively. Three hours of exposure of female C. montrouzieri at 42°C and 2 h exposure at 44°C were lethal for the beetles. Mean longevity of the predator was 33.13?±?1.22 days at 35°C and was significantly shorter as the temperature of the thermal treatments increased from 38^o to 44°C. These results suggest that daily temperature regimes of 35°C combined with 38–40°C for 1–3 h are marginal for the survival and longevity of the C. montrouzieri, whereas temperatures above 42°C are lethal even at short exposure. These results can partly justify the inability of C. montrouzieri to be permanently established in Pakistan environments and could contribute to a pre-evaluation assay of its potential adaptability in such environmental systems.     

Effects of Potassium Humate Fertilizers and Irrigation Rate on Potato Yield and Consumptive Use under Drip Irrigation Method

The current study was carried out at Agricultural College, University of Baghdad in the vegetable farm, Department of Horticulture during 2013 spring growing season. Yield response to irrigation of different crops is of major importance in production planning where water resources are limited. This study aims to determine the effect of different irrigation treatment （deficit irrigation） and potassium humate fertilizer on yield, content of nitrogen, potassium, and phosphor in tuber of potato and water use efficiency in the Abu-Graib Region, Iraq. Potato was grown under drip irrigation with three treatments： irrigation applied when evaporation 75%, 100% and 125% from pan A, and three potassium humate fertilizers： 0, 1.2 and 2.4 kg/ha with three times additions. The seasonal potato evapotranspiration ranged from 267 mm to 372 mm. The drip irrigation treatment had significant effecting tuber yield of potato recorder 29,530, 27,630 and 24,880 kg/ha for 125%, 100% and 75% from pan A evapotranspiration, respectively. Humus fertilizers addition has the lowest value of ETa 309 mm and maximum value of yield 2,930 kg/ha. Water use efficiency （WUE） and irrigation water use efficiency （IWUE） values increased with increasing humus fertilizers, recording 9.92, 14.52, 8.59, 12.42 and 7.51, 10.70 kg/m3 for potassium humate K3 （2.4 kg/ha）, K2 （1.2 kg/ha） and KI （0.0 kg/ha）, respectively. Plants irrigated with 125% from class pans A evaporation, produced a significant increase in N, P and K content in tubers recorder 0.96%, 0.58% and 1.52%, respectively. Potassium humus-fertilizer significant differences among K1, K2 and K3 on high of plants reached 41.52, 50.08 and 56.39 cm, respectively, number of stems/plant 2.69, 3.22 and 3.78, respectively, leaves area index recorder 2.80, 3.35 and 3.73.     

Efficacy of Ceranock Attract and Kill System as a Control Method of Mediterranean Fruit Fly, Ceratitis capitata in Apricot Orchards in Central Iraq

A field experiment was conducted using Ceranock bait station, ＂attract and kill＂ system to combat Mediterranean fruit fly, Ceratitis capitata, in apricot orchards, Central of lraq during the 2013 field season. Control program was implemented in three orchards of mixed apricot varieties. Ceranock traps were hung in each tree of two separate orchards. Delta and McPhail traps were used to monitor Medfly population density in each treated and control orchards. Results indicated that Medfly activity in apricot orchards started during the last week of April coincided with the beginning of maturity for fruits of early varieties. The total of trapped insects in monitoring traps after one week of Ceranock application were 0, 1 and 31 adults for the 1st, 2nd and the control orchards, respectively. Three weeks later and on, the number of trapped adults started to increase dramatically. At the end of apricot season and after 45 days of Ceranock trap application, the number of trapped insects in monitoring traps reached 110, 111 and 2,349 adults/week, respectively, for the 1st, 2nd and 3rd orchard. The use of Ceranock traps reduced Medfly population density by 86%-97%. The percentage of fruit injuries in early maturing varieties were 0.75%, 1% and 34% for the 1st, 2nd and control orchards, respectively. While, late varieties were 2% and 3% for 1st and 2nd orchards, and 69% for the control. The percentage of reduction in fruit damages reached to 95% and 97%, respectively in the 1st and 2nd orchard. The results of this study demonstrate clearly the efficacy of Ceranock bait station, ＂attract and kill＂ system as a control measure for Medfly in apricot orchards.     

梨两个休眠相关MADS-box 基因特征及在其休眠过程中的表达分析

 PpMADS1 和PpMADS2 是从‘酥梨’（Pyrus pyrifolia white pear group‘Suli’）休眠芽转录组 文库筛选的两个与休眠相关的MADS-box 基因序列。为了解序列的特征,对其进行了相关生物信息学分 析,并以‘翠冠’和‘圆黄’梨为试材,用实时定量PCR 技术分析其花芽休眠不同阶段的表达变化。结 果表明：两个基因都具有MADS-box 家族的特征序列MIKC-基序,PpMADS1 和PpMADS2 分别与日本梨 （P. pyrifolia‘Kosui’）休眠相关的两个MADS-box 基因PpMADS13-1 和PpMADS13-2 聚在一起,且单独 聚为一支,与李属植物休眠相关的MADS-box 基因关系最近。在两个品种的休眠过程中,PpMADS1 和 PpMADS2 的表达呈现相似的变化趋势,都有一个表达高峰,但‘翠冠’梨PpMADS1 和PpMADS2 的表 达高峰均出现在11 月15 日,而‘圆黄’梨PpMADS1 的表达高峰延后到12 月30 日,PpMADS2 的表达 高峰出现在12 月15 日。两个品种PpMADS1 和PpMADS2 的表达高峰都出现在内休眠解除之前,随内休 眠解除其表达量下调,在生态休眠阶段表达量维持在较低的水平。据此推测PpMADS1 和PpMADS2 的表 达对梨芽内休眠的解除具有调控作用