Trifolium Alexandrium Research Articles

Effect of Arbuscular Mycorrhiza Fungal Inoculation with Compost on Yield and Phosphorous Uptake of Berseem in Alkaline Calcareous Soil

An experiment was conducted in pots under natural conditions in alkaline calcareous soil to determine berseem (Trifolium alexandrium) yield and P uptake as affected by Arbuscular mycorrhizal fungi (AMF) inoculation with compost prepared from fresh animal dung and rock phosphate. Data indicated that berseem shoot and roots yields increased significantly (P ≤ 0.05) by inoculation of indigenous mycorrhiza (AMF-I) and half dose of compost. Shoot yield increased as 98% and 76% roots yield as 60% and 52% over control and N and K fertilizers. Maximum and significantly (P ≤ 0.05) increased plant N and P uptake by berseem was observed in the treatment inoculated by commercial mycorrhiza (AMF-II) with full dose of compost followed by the inoculation of AMF-II with half dose of compost. Plants uptake of Cu, Mn and Fe was improved significantly (P ≤ 0.05) by the inoculation of AMF-II with half dose of compost, while Zn uptake was increased in the treatment of AMF-II inoculation with full dose of compost. Maximum and significantly (P ≤ 0.05) increased soil spores density of AMF as 27 spores per 20 g soil was noted by inoculation of AMF-I with half dose of compost, while maximum roots infection intensity in berseem was observed by the inoculation of AMF-I with full dose of compost. Results suggest that inoculation of AMF with compost has potential to improve berseem yields and plants nutrients uptake under given soil conditions.

Nutritional evaluation of wheat straw treated with white-rot fungus Crinipellis sp. RCK-SC in Sahiwal calves

Digestibility of wheat straw is limited mainly by lignin in ruminants, and fungal treatment is known to improve its nutritional worth. In the present study, wheat straw, subjected to solid state fermentation with ligninolytic white-rot basidiomycetes fungus Crinipellis sp. RCK-SC for 10 days, was studied with untreated wheat straw for in vitro nutritional parameters like chemical composition, digestibility, gas production and ruminal parameters, followed by in vivo feeding trial in Sahiwal calves. The fungal treatment after 10 days led to significant (P<0.05) decrease in cell wall constituents viz. neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, lignin and cellulose to the extent of 104.0, 121.9, 64.2, 29.97 and 73.9g/kgDM, respectively. Crude protein (CP) and ash contents were increased (P<0.05) by 502.7 and 526.1g/kgDM, respectively, in fungal treated wheat straw (FT-WS) than untreated straw (UT-WS). Further, in vitro gas production (GP24h), in vitro true dry matter digestibility and organic matter digestibility for 48h, calculated metabolizable energy (ME) content, microbial biomass production and short chain fatty acids production were significantly (P<0.05) higher in FT-WS, while in vitro methane production (L) per kg of digestible dry matter was lower (P<0.05) in FT-WS. Ammonia nitrogen and total volatile fatty acids values were also significantly (P<0.05) higher in FT-WS. For in vivo feeding trial, ten healthy male Sahiwal calves (8–12 months) were divided into two groups based on comparable body weights following randomized block design. Control group (T1) was fed with ad libitum chopped wheat straw, whereas in treatment (T2), it was substituted with ad libitum chopped fungal treated wheat straw. Animals in both the groups were supplemented with groundnut cake to meet nitrogen requirement and green berseem (Trifolium alexandrium) forage to fulfill their vitamin A requirements. Digestibility of nutrients for DM, OM, CP, ether extract, NDF, ADF, hemicellulose, cellulose and total carbohydrates were significantly (P<0.05) higher in T2 compared to T1 group. Moreover, daily DM, digestible crude protein (P<0.01) and ME intakes were also higher (P<0.05) in T2 with higher (P<0.05) nitrogen retention (P<0.05), higher average daily gain in body weight and feed conversion ratio. This study suggested that the bioconversion of wheat straw using Crinipellis sp. RCK-SC holds potential in upgrading its nutritional value for feeding growing calves.

Nutritional evaluation of wheat straw treated with Crinipellis sp. in Sahiwal calves

Wheat straw was subjected to solid-state fermentation (SSF) with lignolytic white-rot fungus (WRF) Crinipellis sp. for 5days to improve the nutritive value and digestibility. The fungal treatment caused a significant (P < 0.05) decrease in cell wall constituents viz., neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, lignin, and cellulose to the extent of 10.4, 11.2, 8.7, 8.7, and 12.1%, respectively, with increase (P < 0.05) in crude protein (CP) (51.6%) and ash (25.8%) contents in fungal treated wheat straw (FT-WS) than untreated wheat straw (UT-WS). Further, in vitro gas production, in vitro true dry matter digestibility and in vitro true organic matter digestibility at 48h, metabolizable energy (ME) content, microbial biomass production, and short-chain fatty acids synthesis were significantly (P < 0.05) higher in FT-WS. In vivo feeding trial in 10 Sahiwal calves (8-12 months) comprised of (1) control group (T1) fed with ad libitum chopped UT-WS and (2) treatment group (T2) offered with ad libitum chopped FT-WS, in addition to supplementation of groundnut cake and green berseem (Trifolium alexandrium) forage to both groups. Digestibility of nutrients for dry matter (DM), organic matter, CP, NDF, ADF, hemicellulose, cellulose, and total carbohydrates were significantly (P < 0.05) higher in T2 compared to T1. Moreover, daily DM (P < 0.05), digestible crude protein (P < 0.01), and ME intakes were also higher (P < 0.05) in group T2 with higher (P < 0.05) nitrogen (N) retention, which resulted in significantly (P < 0.05) higher average daily gain in body weight (135 vs. 102 g/day). It was concluded that SSF with WRF Crinipellis sp. holds potential in upgrading the nutritional worth of wheat straw for feeding growing calves.

Study of Single and Combination Application of Cover Crops and Their Removal Time on Weed Suppression in Sugar Beet Fields

In order to study the effect of different combinations of cover crops and time of their removal on weeds population in sugar beet fields, an experiment was conducted at the Iranian Research Institute of Plant Protection, . The study was based on two factorial experiments with randomized complete blocks design with four replications. Treatments in first experiment were type of cover crop including: 1) X Triticosecale wittmack, 2) Hordeum vulgare, 3) Trifolium alexandrium), 4) Raphanus sativus and removal times including: 1) at four-leaf sugar beet stage, 2) at eight-leaf stage of sugar beet. In the second experiment, different combinations of cover crops were evaluated. Treatments were cover crop combination including: 1) Hordeum vulgare & Raphanus sativus, 2) X Triticosecale wittmack & Raphanus sativus, 3)Hordeum vulgare & Trifolium alexandrium, 4) X Triticosecale wittmack & Trifolium alexandrium and removal time of cover crops (as the same of the first experiment). The results showed significant effects of different cover crops and their removal times on weeds dry weight and population. Between treatments, combination of X Triticosecale wittmack & Trifolium alexandrium had the lowest weed dry weight and population when removed at four-leaf stage of sugar beet.

Technical Note: Effects of tethering on herbage selection, intake and digestibility, grazing behavior, and energy expenditure by Boer × Spanish goats grazing high-quality herbage1

Twenty-four yearling Boer x Spanish goats were used in a crossover experiment to determine the effects of tethering on herbage selection, intake and digestibility, grazing behavior, and energy expenditure (EE) with high-quality herbage. Four 0.72-ha paddocks of wheat (Triticum aestivum) and berseem clover (Trifolium alexandrium) were grazed in the spring. Each paddock hosted 6 animals, 3 with free movement and 3 attached to a 3-m tether that was moved daily and provided access to an area of 28.3 m(2). One animal of each treatment and paddock was used to determine herbage selection, fecal output, or grazing behavior and EE. Herbage DM mass in tethered areas before grazing averaged 2,649 and 2,981 kg/ha in periods 1 and 2, respectively. The CP concentration in ingesta was greater (P < 0.05; 23.1 and 20.3 +/- 0.82%) for free vs. tethered animals, although in vitro true DM digestion (75.7 and 76.5 +/- 1.20%, respectively) did not differ (P > 0.05) between treatments. Intake of ME based on in vitro true DM digestion and fecal output was greater (P < 0.05) for free vs. tethered animals (12.7 and 10.4 +/- 0.89 MJ/d). No treatment effects were observed (P > 0.05) for time spent ruminating or grazing (405 and 366 +/- 42.5 min/d, respectively), although mean EE was greater (P < 0.05) for free vs. tethered animals (633 and 512 +/- 27.4 kJ/kg of BW(0.75) for free and tethered, respectively), with differences (P < 0.05) between treatments at each hour of the day. Tethering animals may be acceptable to model those with free movement for some measures such as ingesta composition but appears inappropriate for others, such as energy metabolism.

Cytogenetic analysis of somaclonal variation in regenerated plants of Berseem clover (Trifolium alexandriumL.)

Abstract The potential of somaclonal variation was studied in Berseem clover (Trifolium alexandrinum L.) which is one of the important forage plants of Iran, cultivated in different regions of the country. Different tissue culture media and different sources of explants were used to regenerate plants. Petiole and inter-node explants were able to produce callus. Good callus growth occurred in the MS media having 2 mg/l NAA+ 30 gm sucrose. The calli of MS media having 0.5 mg/l NAA+0.5 mg/l KIN could produce plants. The roots were produced in the MS media having 0.1 5 mg/l BAP+1 mg/l IAA which were used for further analysis. Karyotypic analysis of Berseem clover showed the presence of 2n = 2x = 16 chromosome number having 7 pairs of metacentric and 1 pair of sub-metacentric chromosomes. The size of chromosomes ranged from 2 ±0.62 μm to 3.66 ±0.18. Cytogenetical analysis of the tissue culture regenerated plants showed the presence of different somatic chromosome numbers ranging from 2n = 16 to 2n = 48, the la...

Cover Crop Effects on Infiltration, Soil Temperature, and Soil Moisture Distribution in the Canadian Prairies

Excess root zone soil moisture resulting from annual precipitation in excess of crop water requirements negatively affects crop yields. A field study was conducted in the 2005 and 2006 seasons on sandy loam soils to investigate the influence of berseem clover (Trifolium alexandrium L.) cover crop in oats (Avena sativa L.) on soil temperature, infiltration, and soil moisture redistribution within the growing season and during the fall to spring seasons. A 4-year crop rotation experiment to investigate farming with fewer chemicals was used to grow oats in a no-till cultivation system with and without the cover crop. The total and unfrozen water contents were measured in the field using neutron moisture meter and time domain reflectometry, respectively, at 0.2-m intervals from the surface to 1.8-m deep, plus a 0.1-m measurement depth. The cover crop significantly reduced soil moisture during the growing season resulting in significantly lower biomass yields (6146 kg ha-1 combined biomass for oats and berseem clover, vs. 7327 kg ha-1 for oats alone). By mid-August 2005, the cover crop treatment had 34.6% lower water content (0.17 vs. 0.26 m3 m-3) within the 0.0- to 0.7-m root zone depth compared to the non-cover crop. During the fall, the soil profile in the cover crop treatment was 3C warmer, thus delaying soil freezing and leading to a shallower depth of the frozen soil layer (0.4 vs. 0.6 m) in March 2006. During the spring, the cover crop treatment warmed and thawed earlier enabling more snow melt infiltration and deep percolation. Areas experiencing excess soil moisture could use annual cover crops as a means for reducing excess soil moisture during the summer growing season and avoiding accumulation of soil moisture during the fall, winter and spring seasons.

Allelopathic potential of Trifolium resupinatum L. (Persian clover) and Trifolium alexandrium L. (Berseem clover)

This experiment was conducted in order to determine if Persian clover (Trifolium resupinatum) and Berseem clover (Trifolium alexandrium) contained water‐soluble and methanol‐soluble constituents that could affect the seedling growth of four test species; namely, Amaranthus retroflexus, Convolvulus arvensis (field bindweed), Secale cereale, and Sinapis arvensis (wild mustard). The above‐ground tissues of the Persian and Berseem clover plants were collected during the vegetative growth stage and oven‐dried. Three concentrations of aqueous and methanolic extracts were used at full‐strength (33.3 g L−1), half‐strength (16.7 g L−1), and quarter‐strength (8.3 g L−1). Distilled water was used as the control. The weed seeds were placed in Petri dishes containing the legume extract or distilled water (control). The seedling growth of the weed species declined with the increasing concentration of the clover extracts. Wild mustard exhibited the highest sensitivity to both the legume extracts. Compared to the aqueous extract, the methanolic extract caused a greater decline in the seedling growth of the weeds. Berseem clover was the stronger inhibitor of the weed seedling growth, as compared to Persian clover. Therefore, the amounts of allelochemicals present might differ in these two clover species. Field bindweed showed the least sensitivity to both the legume extracts. Field bindweed showed more tolerance to the allelochemicals produced by the clover species.

Molecular characterisation of a mycorrhizal inoculant that enhances Trifolium alexandrium resistance under water stress conditions

The occurrence of drought is an economically important problem in Morocco. The use of mycorrhizal technology offers a possibility to overcome this problem. A mycorrhizal fungal inoculum “Aoufous Complex” isolated in Morocco was shown to enhance Trifolium alexandrium resistance in water deficit situation. The efficiency of this inoculum was confirmed in this study. In order to identify this inoculum, specific primers were used to amplify the 18S subunit. The AluI RFLP typing of the PCR products revealed a single pattern showing no diversity. Phylogenetic analyses of seven sequences including other glomeromycetes allowed an unambiguous identification of the “Aoufous Complex” as Glomus mosseae strains.

Influence of Varying Dry Matter and Molasses Levels on Berseem and Lucerne Silage Characteristics and Their In situ Digestion Kinetics in Nili Buffalo Bulls

Influences of forage DM and addition of cane molasses on silage characteristics of berseem (Trifolium alexandrium) and lucerne (Medicago sativa) and their ruminal digestion kinetics in Nili buffaloes were studied. Berseem and lucerne fodders (at one tenth bloom) were ensiled with wheat straw in laboratory silos to achieve 20, 30, 40% forage DM and without wheat straw (control); each forage DM level was supplemented with 2, 4 and 6% of cane molasses at ensiling. The pH and lactic acid contents of berseem and lucerne silages were affected by both forage DM and addition of molasses. Dry matter, CP and true protein (TP) of berseem and lucerne silages were affected by forage DM at ensiling but were not affected by the addition of cane molasses. Higher DM, CP and TP losses were observed when berseem and lucerne fodders were ensiled either without wheat straw or with wheat straw to achieve 20% and 40% forage DM at ensiling compared with 30% DM at ensiling. Fiber fractions (NDF, ADF, hemicellulose and cellulose) of berseem silage and lucerne silage were significantly increased with increasing forage DM at ensiling. Addition of cane molasses did not affect the DM, CP, TP and fiber fractions of both berseem and lucerne silages. Berseem and lucerne ensiled at 30% DM with 2% cane molasses were screened for comparative ruminal digestion kinetics with their respective fodders. Addition of wheat straw to berseem or lucerne fodder at ensiling depressed DM and NDF ruminal degradability. However, ruminal lag time, rate of degradation and extent of digestion of silages were similar to their respective fodders. In conclusion, berseem and lucerne could be ensiled with wheat straw to increase their DM to 30% along with 2% molasses for buffaloes.

Non-traditional Straws: Alternate Feedstuffs for Ruminants

The nutritive value of 4 straws, obtained after thrashing of seeds from fodder crops, was assessed as complete feed for ruminants. Sixteen male Murrah buffaloes (liveweight 365.8±19.5 kg), were divided into 4 equal groups and offered ad lib. straw of either Trifolium resupinatum, Trifolium alexandrium, Medicago saliva or Lolium perenne, supplemented with minerals and vitamin A, for 40 days in a completely randomized design. Simultaneously, each straw was offered to 3 rumen fistulated male buffaloes in order to assess the biochemical changes in the rumen. Compared to other straws M. sativa straw had higher (p<0.05) organic matter (OM), crude protein (CP), acid-detergent fiber (ADF) and cellulose content. L.perenne had the highest (p<0.05) hemicellulose and lowest (p<0.05) CP and acid-detergent lignin (ADL) content. T. resupinatum had the lowest concentration of cell wall constituents (CWC). The digestibility of nutrients of T. resupinatum and L. perenne straw was similar, but higher (p<0.05) than that of other straws. Msativa straw showed highest (p<0.05) digestibility of CP. The highest OM digestibility of T. resupinatum and CP digestibility of M. saliva were responsible for highest (p<0.05) total volatile fatty acids and trichloroacetic acid precipitable nitrogen in the strained rumen liquor. The digestible crude protein (DCP) was highest (p<0.05) in M. sativa followed by that in T. alexandrium. The total purine derivatives excreted in urine varied from 0.22-0.32 mmol/kg W 75 /d. The efficiency of microbial protein synthesis indicated that OM of straws of M. sativa and that of T. alexandrium was used more (p<0.05) efficiently. The microbial protein synthesized was highest in T. resupinatum, but statistically similar to other groups. The values for N-retention and apparent biological value were highest for L. perenne, though comparable with that of M. sativa and T. alexandrium. The available metabolizable energy (ME) was highest (p<0.05) in T. resupinatum followed by that in L. perenne and lowest in M. sativa. It was concluded that all the straws, supplemented with minerals and vitamin A, could be fed exclusively to adult ruminants with no adverse affect, as animals were able to maintain body weight (372±20.1 kg).

Biomass production and nutritional levels of berseem ( Trifolium alexandrium) grown under elevated CO 2

There is little available information about the effect of elevated CO 2 on the growth and mineral nutrients of fodder crops. To investigate the changes in vegetative biomass and nutrient concentration of berseem ( Trifolium alexandrium L.), an important forage legume, was grown in ambient (360 μl l −1) as well as elevated (600 μl l −1) CO 2 conditions from germination onwards in open top chambers. Elevated CO 2 increased the leaf size, plant height and fresh and dry mass of shoots. There was more partitioning of photosynthates towards the growth of new branches than towards the growth of leaves. Leaf nitrogen, soluble proteins, calcium, iron and nitrate reductase (NR) activity decreased in elevated CO 2 while leaf carbon and phosphorus contents increased. The results suggest that berseem grown in elevated CO 2 throughout the crop season can produce more fodder in less time. The study concludes that elevated CO 2 may increase the fodder production by 30–35% but will adversely affect the nutritional quality of the forage due to reduction in nitrogen, protein, calcium and iron concentration in leaves on a unit dry weight basis. On a unit area basis, however, there will be an increase in total nutrient content, including nitrogen, due to increased fodder biomass in elevated CO 2.

Production potential, soil health, water productivity and economics of rice (Oryza sativa)based cropping systems under different nutrient sources

A field experiment was conducted during 200405 to 200809 at Jabalpur, Madhya Pradesh to study the effect of chemical fertilizers, organic manures (ONM) and integrated (50:50) nutrient management (INM) practices on the production potential, soil fertility, water productivity and economics of 4 rice ( Oryza sativa L.)- based cropping sys- tems involving durum wheat ( Triticum durum Desb.)-sunhemp ( Crotolaria juncea L.), potato ( Solanum tuberosum L.)-okra ( Abelmoschus esculentus L.), berseem ( Trifolium alexandrium L.) and vegetable pea ( Pisum sativum L.) and sorghum ( Sorghum bicolor L. Moench). The productivity of crops in these cropping systems was higher when chemical fertilizer was used compared to ONM or INM in all the years of experimentation. In the initial years, ONM recorded a significant reduction in yield. Of the different rice based cropping systems, rice-potato-okra gave the highest rice equivalent (REs), while rice-wheat-GM gave the least REs. At the end of 5 cropping cycles, applica- tion of organic manures resulted in higher soil organic carbon, available N, P and K than the chemical fertilizers. Maximum beneficial micro-organisms were recorded under organic nutrient management (ONM) after completion of 5 crop cycles and the bulk density of soil was also lowered significantly in ONM. The B:C ratio was higher for chemical fertilizers in case of rice- durum wheat-green manuring (3.6) and rice-potato-okra (3.1) due to lesser cost of cultivation.

Performance of soybean (Glycine max)-based cropping sequences under organic, inorganic and integrated nutrient supply systems in a Vertisols

Experiments were conducted at Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh during 200405 to 200809 (five years) with the objective to develop efficient crop and soil management options for organic farming and their after effects on productivity and sustainability of 4 soybean {Glycine max (L.) Merr.}-based cropping sys- tems with wheat {Triticum aestivum (L.) emend. Fiori &amp; Paol}, berseem (Trifolium alexandrium), mustard {Brassica juncea (L.) Czern &amp; Coss.} and chickpea {Cicer arietinum (L.)} under organic, inorganic and integrated nutrient supply system. In the first year of study, inorganic nutrient supply system (INS) recorded markedly higher yield in all the cropping systems. However, from the second year onwards, integrated plant nutrient supply system (IPNS) produced higher yield in all the four cropping systems studied and found better than INS. Production in all the four cropping systems with organic manuring alone (ONS) was significantly lower than with INS, although the differ- ences decreased as the cropping systems progressed over years. Organic farming system can be profitable only if a price premium of 20% or above is provided. From the view point of soil fertility, IPNS was the best followed by organic nutrient supply system (ONS), while the application of chemical fertilizer alone (INS) recorded the lowest values of available N, P and K and bacterial count.

Effect of Agronomic Practices on Fresh Forage and Seed Yield of Barseem Trifolium alexandrium L.

Effect of Agronomic Practices on Fresh Forage and Seed Yield of Barseem Trifolium alexandrium L.

Raised and sunken bed technique for agroforestry on alkali soils of northwest India

AbstractMany forest tree and fruit species can be raised on highly alkali soil (pH &gt; 10) but some of them such as pomegranate (Punica granatum) are unable to tolerate water stagnation. To avoid water stagnation problems during the monsoon the raised and sunken bed technique has been found suitable for agroforestry practices on highly alkali soil. One fruit‐yielding pomegranate and one oil‐yielding salvadora (Salvadora persica) plantation species were successfully grown on raised bunds to avoid water stagnation and rice–wheat and berseem–kallar grass rotation were grown on sunken‐beds constructed for the purpose. The experiment was initiated in 1996 and the above two crop rotations were followed for two consecutive years starting in the summer season. Results of these experiments have also shown that good growth of plantations, on an average 4·3 to 4·9 t ha−1 rice (salt tolerant var. CSR‐10) and 1·2 to 1·4 t ha−1 wheat (KRL 1–4), were obtained in sunken beds. In another rotation 21·3 to 36.8 t ha−1 fresh forage of kallar grass (Leptochloa fusca) and 44·9 to 47·8 t ha−1 fresh forage of berseem (Trifolium alexandrium) were obtained. After two years of the experiment, soil amelioration in terms of reduction in soil pH was significant. The effect of plantation in reducing soil pH showed that the pomegranate and salvadora both helped in reduction of soil pH, but the latter due to its well‐developed lateral root system was more efficient in lowering the soil pH even at lower depths. The reduction in soil pH by the berseem–kallar grass rotation was better than under rice–wheat rotation. Copyright © 2001 John Wiley &amp; Sons, Ltd.

Cover Crops for Saline Soils

A 3-year study was conducted in the Central Valley of California to evaluate 125 prospective winter-growing cover crops for growth and nitrogen productivity in saline soils. Soil saturation paste electrical conductivities (ECes) in the surface 15 cm averaged 7dS m -1 at fall planting and 5.3 dS m -1 at spring harvest dates of each experiment. Species evaluated varied substantially in plant height. In general, the tallest plants were the Brassica species, which consistently grew to over 1.4m. Annual grasses (barley, rye, triticale and wheat) averaged about 1.0-1.3 m in each year. Of the legume species screened, heights were greatest for Hedysarum coronarium, Trifolium alexandrium, Vicia spp., and Medicago polymorpha and truncatula, averaging 59, 47, 39, 38 and 37 cm, respectively, over all experiments. About one third of the species screened produced crop cover in excess of 90% in each year. Groups of plants with consistently high crop cover percentages included various species/accessions of Brassica, Hedysarum, annual grasses, cool-season annual medics, Medicago polymorpha and Medicago truncatula, and two annual clovers, Trifolium alexandrium cv 'Multicut' and rose clover, Trifolium hirtum cv 'Hykon.' Total above-ground plant dry weights were highest for Brassica spp., which produced twice as much biomass as the annual grass species, and roughly four times as much dry matter as any of the legume species. Hedysarum, Lana and Namoi woolypod vetch, purple vetch, berseem clover, and several of the annual medic species consistently had the highest biomass among the legumes.

An evaluation of agriculture, forestry and agroforestry practices in a moderately alkali soil in northwestern India

Productivity, sustainability and economics of agriculture, forestry and agroforestry land use practices were compared over a six year period in a split plot experiment on a moderately alkali soil of the Central Soil Salinity Research Institute, Karnal, India. Three commercial trees of the area formed the main plot treatments and four crop sequences were the sub-plots. The trees were: poplar (Populus deltoides), Acacia (Acacia nilotica) and Eucalyptus (Eucalyptus tereticornis), and the crop sequences were (1) rice (Oryza sativa)-wheat (Triticum aestivum) for four years followed by guinea grass (Panicum maximum)-oats (Avena sativa) for two years; (2) rice-Berseem (Trifolium alexandrium) for four years followed by cowpea (Vigna unquiculata)-Berseem for two years; (3) pigeonpea (Cajanus cajan)/sorghum (Sorghum bicolor)-mustard (Brassica juncea) for three years followed by turmeric (Curcuma longa) for three years and (4) no intercrops (only trees). Eucalyptus and poplar gained maximum height, girth and woody biomass in six years when they were intercropped with rice crops in sequences 1 and 2. Acacia attained maximum growth in the absence of intercrops. Protein content in guinea grass was more under tree canopies than in the open. Soil amelioration during five years followed the order: Acacia based system > poplar > Eucalyptus > sole crops. The benefit-cost ratio was heighest (2.88) in poplar based system and minimum (1.86) in Acacia based system. The study indicated that growing trees and agricultural crops together is a better land use option in terms of productivity, maintenance of soil conditions and economics.

Evaluation of three mediterranean forage legumes for biological nitrogen fixation

Abstract Continuous grain cropping in many areas of the world has reduced soil N levels to a degree such that agricultural production is now largely dependent upon nitrogen fertilizer. Through the identification of highly effective legume and Rhizobium strain combinations, however, increased production of protein‐rich livestock forage and green manure is possible. Three common Mediterranean legumes, Lupinus albus, Medicago truncatula, and Trifolium alexandrium were chosen to be tested for symbiotic N‐fixation ability with various available strains of Rhizobium. Greenhouse and growth chamber experiments were conducted for six weeks to evaluate shoot, root, and nodule dry weight, nodule number, nodule acetylene reduction activity, and total plant N. For L. albus, four single strains, 96A5, 96A19, 96B15, and 96B23, and one commercially available multiple strain ‘H’, produced acetylene reduction activity from 100 to 190 μmoles ethylene evolved/h/gdw of nodules. Since plant dry weights and total plant N values...

Time and energy budgets of alfalfa pollinating beesMegachile nana bingh andMegachile flavipes Spinola (Hymenoptera: Megachilidae)

Laboratory measurements of physiological energetics were coupled with the field observations on time budget/energy intake ofMegachile nana andMegachile flavipes to estimate the daily energy budget. The energy budget varied from one day to another, and crop to crop. In general, the foraging profitability/attractibility was in the following order for both the species:Parkinsonia aculeata> Medicago sativa> Trifolium alexandrium. The studies revealed the competitive superiority ofParkinsonia aculeata overMedicago sativa andTrifolium alexandrium.