Caspian Journal of Environmental Sciences
Volume:5 Issue: 1, Winter 2007

Duopoly game theory is applied to the wood industrial markets (sawnwood and pulpwood markets) in the North of Iran. The Nash equilibrium and the dynamic properties of the system based on marginal adjustments are determined. The probability that the Nash equilibrium will be reached is almost zero. The dynamical properties of sawnwood and pulpwood prices derived via the duopoly game model are found also in the real empirical price series.

The genetic variation and diversity among fifty-eight polyvoltine silkworm genotypes was estimated by using ten economic traits. The results revealed that the single shell weight showed higher genetic variation such as PCV% (17. 20%) ، GCV% (12. 93%) ، and heritability (56. 5%) followed by single cocoon weight، shell ratio and matured larval weight. The D2 (Mahalonobis? distance) statistics revealed nine clusters with substantial inter and intra cluster distances. The genotypes included in different clusters varied from 1 to 16. The genotype Pure Mysore was included in isolated cluster indicates its longer adaptation. The genotypes included in cluster VIII and IX showed optimum genetic distance along with higher cluster mean emphasised for utilization in the silkworm breeding.

his paper seeks to understand the influence of different levels of fertilizer nutrients on annual yield of cardamom in Cardamom Hill Reserves (CHR) under rain fed situation. Field experiment conducted at CRS, Pampadumpara during 1994-2002 on nutrient levels with sources revealed that increasing the levels of nitrogen, phosphorus and potassium had increased the yields of cardamom up to 125: 125: 200 kg ha-1. Application of fertilizer nutrients at the present level of recommendation (75: 75: 150 kg NPK ha-1 yr-1) in the form of urea, single super phosphate and muriate of potash along with 0.5 kg neem cake per plant had not increased the yield significantly over the control. Application of fertilizer nutrients at the rate of 125: 125: 200 kg ha-1 yr-1in two splits (just before and after summer monsoon) increased the yield significantly under Pampadumpara rainfall climatology. Among N, P and K, it appears that K is the most important as indicated by a larger absolute value than that of N and P. Therefore application of fertilizer K is a must to increase the cardamom yield in CHR system. However, rainfall during summer months and number of rainy days had pronounced effect on the production of cardamom. Among rainy seasons (SWM, NEM and SR), SR played significant role in increasing the cardamom yield. Higher than the average SR (366mm) followed by SWM (1162mm) found to influence the yield significantly. The reason for the higher yield by summer rainfall could be due to increased growing season soil moisture which is essential for the growth and panicle initiation and subsequent development of flowers and capsule setting. The recent all India droughts have very little influence on the rainfall climatology of cardamom hill reserves during the period of South West monsoon and therefore the yield was not affected by all India droughts but the summer months? rainfall and its distribution.

A bivoltine silkworm hybrid, KA x NB4D2 was treated with the juvenoid R394 (Ethyl-9 cyclohexyl-3,7-dimethyl-2,4-nonadienoate) at a dose of 0.039 nl/larva at 24, 48, 72 and 96 h of 5th instar for silk yield improvement. Treatment specific significant increase was observed in the cocoon and shell weight with no such marked variation in the shell percentage. Notable changes were also seen in traits such as larval duration, larval weight and silk gland weight in the treated silkworm. Total protein, total carbohydrate and total lipid were analyzed in the posterior silk gland (PSG), haemolymph and fat body of fully grown larvae. The result indicated that the content of these primary metabolites varied significantly in the selected tissues depending on the time of juvenoid application. The highest content of protein in the haemolymph and silk gland was in the larvae treated at 72 h whereas the fat body protein content was lowest in the same group. The total carbohydrate was recorded lowest in the 72 h treated larvae as against the highest in the control both in haemolymph and fat body with no significant change in PSG. The total lipid content did not show any notable variation in the concentration on juvenoid administration except in the silk gland treated up to 72 h which showed a decline. The result indicates that the juvenoid induces tissue specific responses in terms of turnover in primary metabolites.

Composition and structure of a three-storied Fagus orientalis-dominated forest was investigated in the Caspian forests, north of Iran. Circular sampling plots of 1000 m2 occupied by advance growth and natural regeneration were randomly chosen where the initial cuttings (with shelterwood aim) were performed. Abundance of species at different growth stages and quality of seedlings and saplings were registered and basal area and standing volume determined. The measurements were carried out before the first shelterwood cutting (in 1974) and after the last shelterwood cutting (2004). The results after 30 years (in 2004) revealed that frequency, basal area and standing volume significantly enhanced for beech and reduced for hornbeam but did not statistically differ for alder, maple and other species. Sapling and thicket groups were observed in parts of the investigated site and where the mature trees were not felled. Generally, the research area was converted into an irregular uneven-aged 2-4-storied forest, owing to recruits, advance regeneration, aged trees and small and large pole groups maintained through the forest.

Transpiration, as one of the components of hydrological cycle, has not been paid enough attention yet, while it is necessary for sound utilization of rangelands, mostly located in the arid and semiarid regions. The comparison of the different kinds of rangelands species in terms of transpiration rates provides range managers the required information to achieve optimal forage production for a given input precipitation. The present study is a preliminary comparison in transpiration between two important Iranian rangeland species viz. A. intermedium and A. elongatum. The amounts of daily evapotranspiration from aforesaid species of which 4?5 shoots were initially planted in small polyethylene pots with surface area of 50.27 cm2 in five replicates were measured using weighing technique for a period of 33 days under relatively natural conditions. The amounts of daily transpiration of A. intermedium and A. elongatum were respectively varied from 1.4 to 9.4 and 1.5 to 9.1 milliliter. The results of the statistical analyses showed that there is no a significant difference between the amounts of transpiration for the two species on dry matter basis and therefore, the species may have the same value in rangeland improvement from transpiration point of view.

Three bacteria from a tobacco industry effluent and one from a sewage sample were isolated on a medium comprising of 1% tobacco powder as sole source of nutrients. Bacteria isolated from the industrial waste water were identified as Bacillus cereus, B. alvei and B. circulans. While, Lactobacillus sp. was isolated from the sewage sample. The bacteria were optimized for various growth conditions in a medium comprising of aqueous extract of 1% tobacco powder in MIII. Provision of 0.1% molasses (MIII) enhanced growth of B.cereus as compared to its cultivation in MII. Growth of B.cereus up to two weeks in molasses supplemented 1% tobacco powder (MIV) medium resulted into retroprogressive decreases in total suspended matter, ash content and total organic matter. So that at the last sampling period these parameter reduced up to 92%, 82% and 42%, respectively as compared to control values. The bacterial isolates in general and the B.cereus practically appear promising for designing in situ biotreatment plants for tobacco processing units and are likely to add in reducing environmental contamination originating from tobacco allied toxic compounds.

The genetic variation and diversity among fifty-eight polyvoltine silkworm genotypes was estimated by using ten economic traits. The results revealed that the single shell weight showed higher genetic variation such as PCV% (17.20%)، GCV% (12.93%)، and heritability (56.5%) followed by single cocoon weight، shell ratio and matured larval weight. The D2 (Mahalonobis? distance) statistics revealed nine clusters with substantial inter and intra cluster distances. The genotypes included in different clusters varied from 1 to 16. The genotype Pure Mysore was included in isolated cluster indicates its longer adaptation. The genotypes included in cluster VIII and IX showed optimum genetic distance along with higher cluster mean emphasised for utilization in the silkworm breeding.

The successfully breeding of the hybrids 873?874 had settled the problem that the yield was not uniform to the silk quality in silkworm varieties. In this paper, we illuminated the key technology, principle, hints and methods for selection in breeding spring-and-autumn rearing silkworm varieties were analyzed using the procedure of breeding the hybrid of 873?874 as example.