Crop productivity under differently lopped canopies of multipurpose trees in Central Himalaya, India

Ficus species are multipurpose trees well known by rural populations in Sahelian and Sudanian zones of Africa. Their uses are well documented but their amenability for vegetative propagation has not been extensively studied. This paper compares the rooting ability of stem and aerial root cuttings from thirteen Ficus species found in West Africa. It highlights the differences between species belonging to the sub-genera Sycomorus and Urostigma. The former show no capacity to propagate from cuttings whereas the latter, with epiphytic development, can be propagated by cuttings, although this capacity varies among species. Thus, F. thonningii, F. leprieurii and F. ovata are easily propagated, while F. platyphylla and F. elasticoides are propagated with difficulty. The rooting capacity also varies depending on the cutting material used. It decreases in the following order: long leafless hardwood cuttings (pole) > nodal cuttings > apical cuttings. Rooting potential increases when the cuttings are harvested towards the end of the dry season(March to May). Aerial root can be used for cuttings in all species of the sub-genus Urostigma. The capacity of root cuttings to regenerate is greatest when cuttings are collected at the beginning of the dry season (November). In this case, wound-induced adventitious roots arise at the basal end of the cutting while de novo buds are developed from the cambium at the distal end. The subsequent morphological development is identical to that of a stem cutting. These results clarify and allow the optimal use of the knowledge and methods developed by the indigenous people of the Sahel and could assist and promote fig tree (Ficus sp.) domestication in the dry tropics.This revised version was published online in November 2005 with corrections to the Cover Date.     

Marketing constraints for Eucalyptus from farm lands in India

During the early eighties farmers in north-west India planted Eucalyptus on a massive scale for sale as poles and pulpwood. However, after 1986 farmers in this region have almost stopped growing Eucalyptus, as their experience with its marketing was not a happy one. The pole market got saturated, paper mills did not pay a remunerative price, and fuelwood prices were low and uneconomical. More important, because of legal restrictions on the transport and sale of wood, and other institutional factors, the gap in the farmgate price and the consumer price remained very wide. Wood markets have, on the whole, exploited the farmers, rather than helped them. Due to this, the short period of flirtation with tree crops seems to be over for at least resident farmers in those very areas in north-west India where they had so enthusiastically planted Eucalyptus in the early 1980s.Abbreviations BDO Block Development Officer - Headloaders poor people who collect firewood on their heads from forest lands for consumption and sale - m ha million hectares - Rs Indian Rupee 16 Rs = 1 US Dollar in 1989 - panchayat elected village organisation - pradhan village chief On study leave from the Government of India to the Oxford Forestry Institute, South Parks Road, Oxford, OX1 3RB, U.K. Present address: 17 Ponnappa Road, Allahabad 211001, India     

Trade-offs and synergies in management of two co-occurring specialist squash pests

Journal of Pest Science - Co-occurring herbivorous pests may have shared or divergent responses to plant- and insect- derived cues, creating challenges for effective pest management in...     

Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants

Background

Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed.

Results

Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO₃ (1.0), and MgSO₄ (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained.

Conclusions

The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods.     

Production of hybrids between Cajanus acutifolius and C. cajan

There are many wild species of pigeonpea which are endemic to Australia. These wild species are cross incompatible with cultivated species of Indian origin. Cajanus acutifolius is one such species which does not easily cross with cultivated pigeonpea. Interspecific pollinations lead to hybrid seeds which were semi-shrivelled. Very few seeds germinated to give rise to F1 plants. Backcrossing the hybrid plants to C. cajan, the male parent, gave rise to aborting seeds which did not germinate in vivo hence BC1 plants are obtained after saving the aborting embryos in vitro. BC₁ plants showed normal meiotic pairing, but had low pollen fertility. The reasons for embryo abortion and low pollen fertility in spite of normal meiosis could be due to the effect of wild species cytoplasm. This revised version was published online in August 2006 with corrections to the Cover Date.     

Production and characterization of hybrids between Cajanus cajan × C. reticulatus var. grandifolius

Cajanus reticulatus var. grandifolius, endemic to Australia and a wild relative of the cultivated species, C. cajan, was successfully crossed with the latter as the female parent. The major wild species characters such as persistent stipules, long pod hairs, pod shattering, brown seeds with grey speckles, and presence of seed strophiole were dominant in the hybrid. For growth and branching habit, and leaflet, flower, pod, and seed size, the hybrid was intermediate between the parents. The meiotic cells of the hybrid were found to have quadrivalents, trivalents, univalents,and showed reduced chromosome pairing as revealed by the increased number of rod bivalents per cell at metaphase-I, and stickiness and precocious movement of chromosomes to poles in the second division. In comparison to the parents, the hybrid had fewer pods and seeds. However,these anomalies in the interspecific hybrid are not significant enough to preclude the gene transfer from C. reticulatus to the cultivated species through a sexual route. This revised version was published online in August 2006 with corrections to the Cover Date.     

Reciprocal recurrent selection for multitrait indices in maize

Summary Reciprocal recurrent selection was carried out with two populations of maize (Zea mays L.) having good combining ability. We selected for higher grain yield, early maturity, shorter plant height and lodging resistance. Two cycles were completed in two years (four seasons), by resorting to late planting of S1 lines for recombination in the main season in which top-cross families were assessed. Top-crosses and selfings were made in the off-season. The original and improved versions of the populations and their crosses were evaluated in multilocation trials. The superiority of the population hybrid was 10.3% for grain yield, 5.5% for plant height and 1.8 days to silk. The improved hybrid had delayed leaf senescence and better resistance to lodging and post-flowering stalk rots. Among the yield components, only ear girth showed improvement. Syn 2 of the improved population cross showed a yield reduction of 6.2% in comparison to Syn 1. Intrapopulation gains were not significant except for lodging resistance in one population.     

Bioconcentration of HCH isomers by the ciliate protozoan,Tetrahymena pyriformis under laboratory conditions

Tetrahymena pyriformis, a common freshwater ciliate concentrated the four common HCH (Hexachlorocyclohexane) isomers viz., α, β, δ, and γ to varied extent. Bioconcentration factor [as expressed by the ratio of cellular insecticide in ng mg^?1 (dry weight) to supernatant in ng μL^?1 ranged from 342 to 2260 for α-HCH, 37 to 831 for β-HCH, 326 to 2806 for δ-HCH and from 106 to 1214 ppm for γ-HCH.     

The Influence of Glutathione on Physiological Effects of Lead and its Accumulation in Moss Sphagnum Squarrosum

An attempt has been made to study the physiological andbiochemical responses and to evaluate the bioaccumulationpotential of moss Sphagnum to environmental lead. Supply of0.1 to 100 mM lead acetate caused a loss in chlorophyll andnitrogen content of moss and in nitrate reductase activity in themoss, although the peroxidase activity was increased. Partialrecovery in the above parameters was recorded upon simultaneoustreatment with glutathione. Results also indicate that treatmentwith glutathione increased the bioaccumulation potential bylowering the lead toxicity, which could be the result of inductionof metal binding capabilities of cells as the heavy metal alsoinduced the synthesis of phytochelatins. The moss accumulated asignificant amounts of Pb under both experimental and fieldconditions. The heavy metal accumulated by moss was positivelycorrelated to the soil metal content. The experiments demonstratethat Sphagnum is able to accumulate and tolerate higheramounts of Pb and therefore, it can be used as a bioindicator andphytoremediator of lead contaminated environment.