Breeding system of Solanum integrifolium Poir. with an emphasis on sex potential and intercrossability

Summary The breeding system of Solanum integrifolium has been studied with the view of setting up a breeding programme. Three flower types are distinguished on the basis of style length. The results of crosses among these types have elucidated that only long-style flowers are female-fertile. The medium and short-style flowers are unable to set fruits. Some of the flowers, irrespective of their stylar morphism, also exhibit male sterility which is uncommon in Solanum. The biological significance of the stylar heteromorphism has been discussed in relation to evolutionary trends in the genus and the probable cause of this phenomenon speculated upon.     

Evidence of peste des petits ruminants virus (PPRV) infection in Sindh Ibex (<Emphasis Type="Italic">Capra aegagrus blythi</Emphasis>) in Pakistan as confirmed by detection of antigen and antibody

An outbreak resulting in mortality in Sindh Ibex (Capra aegagrus blythi) was investigated. There was a history of about 36 deaths (both young and adult) during the period of 1 month. Disease appeared in a generalized form, affecting the respiratory and digestive systems. Major lesions were respiratory distress, pustules on and in the mouth, ocular–nasal discharges, and severe diarrhea. The most significant lesion was the oculonasal discharges and diarrhea. Deaths were mainly due to blindness, anorexia, diarrhea, and respiratory arrest. Both adult (mortality = 21) and young (mortality = 15) animals were affected with the disease. Peste des petits ruminants virus (PPRV) antigen was detected in the spleen, lung, lymph node, and swab samples by immunocapture enzyme-linked immunosorbent assay. Spleen and lung samples were also tested and found positive for the presence of F-gene of PPRV by polymerase chain reaction. Thirteen of 20 serum samples from nearby sheep and goats were found positive for antibodies to PPRV. The disease threatened the huge population of ibex in the wild life park, which was spread over a large area, but vaccination of the domestic population of sheep and goats in the surrounding villages appeared to control the disease.     

Characterization of a heterodimeric GH2 β-galactosidase from Lactobacillus sakei Lb790 and formation of prebiotic galacto-oligosaccharides

The lacLM genes from Lactobacillus sakei Lb790, encoding a heterodimeric β-galactosidase that belongs to glycoside hydrolase family GH2, were cloned and heterologously expressed in Escherichia coli . Subsequently, the recombinant β-galactosidase LacLM was purified to apparent homogeneity and characterized. The enzyme is a β-galactosidase with narrow substrate specificity because o-nitrophenyl-β-D-galactopyranoside (oNPG) was efficiently hydrolyzed, whereas various structurally related oNP analogues were not. The K(m) and k(cat) values for oNPG and lactose were 0.6 mM and 180 s(-1) and 20 mM and 43 s(-1), respectively. The enzyme is inhibited competitively by its two end-products D-galactose and D-glucose (K(i) values of 180 and 475 mM, respectively). As judged by the ratio of the inhibition constant to the Michaelis constant, K(i)/K(m), this inhibition is only very moderate and much less pronounced than for other microbial β-galactosidases. β-Galactosidase from L. sakei possesses high transgalactosylation activity and was used for the synthesis of galacto-oligosaccharides (GalOS), employing lactose at a concentration of 215 g/L. The maximum GalOS yield was 41% (w/w) of total sugars at 77% lactose conversion and contained mainly non-lactose disaccharides, trisaccharides, and tetrasaccharides with approximately 38, 57, and 5% of total GalOS formed, respectively. The enzyme showed a strong preference for the formation of β-(1→6)-linked transgalactosylation products, whereas β-(1→3)-linked compounds were formed to a lesser extent and β-(1→4)-linked reaction products could not be detected.     

In-plant activation of root-specific expression of a cytotoxic gene disrupts the development of the root-knot nematode,Meloidogyne javanica

Plant hosts can be engineered to disrupt the development of sedentary plant-parasitic nematodes or proper functioning of the feeding sites the nematodes induce. The use of constitutive promoters to express dsRNAs or nematode inhibitor proteins may be unreliable because of possible silencing or yield penalty from continuous expression in a plant host. This ill-effect can be avoided if a root-specific, nematode-responsive promoter (NRP) is used to drive the target nematode-inhibitory message. This study used the In Plant Activation (INPACT) system to express a barstar-controlled barnase in galls of Meloidogyne javanica and assessed how the engineered tobacco lines affected the growth and development of the nematodes. Of the 11 combinations of four NRPs and the CaMV 35S promoter assessed, the AtCel1 and TobRB7 combinations activated specific expression of split β-glucuronidase (GUS) and barnase genes in and around giant cells. The same NRP combination directed expression of the barnase gene in tobacco roots also constitutively expressing the barstar gene (SPBB transgenic lines). On roots of six T₁ SPBB lines, there was up to 94% reduction in the number of galls with significantly smaller adult females compared to those on wild-type plants. Some of the females on lines SPBB4-1 and SPBB-4-2, for example, were not associated with galls. The results indicated the engineered plants disrupted M. javanica development and demonstrate the potential for controlled and localized expression of peptides, such as those that could block specific effectors, to disrupt initiation, formation, establishment, or proper functioning of feeding cells induced by damaging sedentary nematodes.     

Accumulative effects of humic acid and multinutrient foliar fertilizers on the vegetative and reproductive attributes of citrus (Citrus reticulata cv. kinnow mandarin)

Abstract

Field trials were performed to investigate the effects of humic acid (HA) and multinutrient foliar fertilizer “Micro Power” (MP) coupled with farmer’s practices ( FP ), addressed in single and/or split dose frames at different plant phenological stages on various vegetative, reproductive, and physiological attributes of citrus trees (Citrus reticulata cv. kinnow mandarin). The results exhibited a profound response of treatments on various growth parameters (32.5% increase in plant height, 22.2% increase in fruit set branch^?1, 5.25% decrease in fruit drop percentage, 89.81% increase in fruit yield (kg), etc.) of citrus trees when compared to the control (FP). Likewise, a significant positive response was observed regarding various plant physiological parameters (leaf nutrients, total chlorophyll content, etc.) and physicochemical characteristics (ascorbic acid, total sugars, etc.) of citrus fruits. This study confirmed the reproducibility of HA and MP applications to improve the yield/quality of citrus and can lead to an organically sustainable citriculture.     

Effect of short-term supply of farmyard manure on maize growth and soil parameters in pot culture

Farmyard manure (FYM) improves various soil parameters and to a large extent, the availability of water and nutrient to crops when it is applied to the soil. This study aims to further investigate the short-term effects of different levels of FYM on maize plants and soil parameters. Maize plants grown in pot culture were treated with no FYM (control), recommended NPK (inorganic fertilizers), and FYM at 2, 4, 6, 8, and 10 t ha^?1 along with recommended NPK, and the cultures were analyzed 8 weeks after germination. Soil bulk density and soil pH decreased with the increasing levels of FYM, whereas soil porosity, soil organic matter (SOM), soil water content, plant height, root and shoot yield, and NPK uptake of maize were increased compared with the control or recommended NPK, respectively. The present results indicate that short-term application of higher FYM levels improves soil properties. Furthermore, the application of FYM at only higher rates significantly increases the nutrient uptake of maize plants due to improved soil properties. The supply of different amounts of nutrients increases biomass and nutrient uptake in plants.     

Glyphosate-tolerant cotton in Australia: successes and failures

ABSTRACT

Cotton is an important cash crop grown on 2.5% of the world’s arable land in over 100 countries, and has a 31% share of the world’s fibre market. In Australia, cotton is also a leading crop and contributes around AUD $3 billion to the total agricultural production. Weeds are a major biotic constraint resulting in yield losses of up to 90% and revenue losses of around AUD $100 billion globally and $4 billion to Australian agriculture. Genetically-modified (GM) crops have refashioned the weed management with more dependency on glyphosate. Such overreliance has led to the evolution of 43 glyphosate-resistant (GR) weed populations globally, with 16 species reported from Australia. Such GR weeds along with volunteer glyphosate-tolerant (GT) plants are now decreasing the value of the GM crops and forcing growers to spend more time and effort, and investment in their management. Weed management strategies need to be diversified and integrated with non-chemical methods and alternative herbicides not only to achieve efficient control, but to reduce the rate of evolution of GR weeds. In future, research is needed to improve integrated weed management through development and use of competitive and multiple herbicide-tolerant (HT) crops, organic herbicides, bio-herbicides, RNAi technology and robotics.     

Aflatoxins and ochratoxin A contamination in rice,corn and corn products from Punjab,Pakistan

In present study, a total of 275 retail cereal samples including rice, corn and corn products was analyzed for the presence of aflatoxins and ochratoxin A (OTA) using HPLC equipped with a fluorescence detector. The data has shown that 38 out of 68 samples of rice, 37/105 of corn and 43/102 samples of corn products have been found contaminated with AFs, average level of AFB₁ and total AFs, 8.23 and 19.54, 7.90 and 12.08, and 5.47 and 7.85 μg/kg, respectively. Furthermore, 34, 28 and 26 numbers of rice, corn and corn product samples were found to be contaminated with OTA with an average level of 12.94, 5.29 and 3.69 μg/kg, respectively. The samples of rice, corn and corn products found above the permissible European Union (EU) limit for AFB₁ and total AFs were 18, 13 and 14 and 28, 14 and 20%, respectively; however, the samples of rice, corn and corn products above the EU limit were 40, 14 and 15%, respectively.     

Prospects of raising Sahiwal cow calves for veal production under tropical environment

The objective of present study was to evaluate the growth potential of Sahiwal calves for veal production on whole milk or whole milk and milk replacer combined in a ratio of 50:50 (MMR). For this purpose, 48 Sahiwal calves (both male and female) were assigned to four dietary treatments having 12 animals/treatment. Calves in the treatments A and B were offered whole milk at 15 or 20 % of their body weight (BW), respectively, up to day 84 adjusted on weekly basis. The calves in treatments C and D received the same amount of milk as in treatments A and B until day 21, respectively, after which 50 % of the milk offered was replaced with a blend of chickpea (Cicer arietinum) flour and vegetable (corn) oil mixed in water (MR) until day 84. The constituted MR had 3.1, 2.8, and 14.3 %, CP, EE, and DM, respectively. The growth and intake data were analyzed using repeated measures analysis, with MIXED Procedures of SAS in a 2?×?2 factorial design. The two factors were feeding level and feeding source. Calves offered whole milk grew faster (P?<?0.05) and had greater weaning weights (P?<?0.05) than those offered MMR (606.4?±?18.1 vs 331.3?±?18.1 g/day and 70.4?±?1.5 vs 47.8?±?1.5 kg, respectively). Greatest daily BW gain (656?±?26 g/day) and weaning weight (74.6?±?2.1 kg) were observed in calves given treatment B while the lowest production cost/kg of BW gain (≈US$3.6?±?0.2) was observed in calves given treatment A. The daily BW gain of calves fed milk ad libitum was 716?±?40 and 836?±?40 g/day, during 5–8 and 9–12 weeks, respectively. The number of days calves exhibited scours was higher in calves offered MMR than those offered whole milk. Replacement of 50 % milk with a blend of chickpea flour and vegetable oil, as an alternative to milk replacer, did not support growth equivalent to whole milk and was not effective in reducing feeding cost during the weaning period. Sahiwal calves may have promise for being raised for veal production under tropical environments.