Effects of localized defoliations on female inflorescences in mountain birch, Betula pubescens ssp. tortuosa

1989 ◽  
Vol 67 (2) ◽  
pp. 334-338 ◽  
Author(s):  
Juha Tuomi ◽  
Timo Vuorisalo ◽  
Pekka Niemelä ◽  
Erkki Haukioja
Keyword(s):  
Betula Pubescens ◽  
Mountain Birch ◽  
Final Weight ◽  
Final Length ◽  
Short Shoots ◽  
Leaf Flush ◽  
Biomass Increase

Two experiments were done to test how the removal of foliage from small branches in mountain birch, Betula pubescens spp. tortuosa, may influence the biomass increase of female inflorescences that emerge from reproductive buds on short shoots. First, all the leaves on small twigs were removed shortly after leaf flush in June. Defoliated twigs included on average of five leaves and two reproductive short shoots. Effects of the treatment on the final length and mass of female catkins were studied in August by comparing defoliated twigs to undefoliated ones of the same trees. Second, a similar experiment was carried out by defoliating larger branches with an average of 150 leaves and 56 short shoots and by comparing defoliated branches to adjacent undefoliated branches. The first treatment reduced final weight of inflorescences by about 17% and the second treatment by about 18%. Localized defoliations can thus have limited effects on the biomass increase of female inflorescences. Short shoots are therefore partially autonomous reproductive units that are integrated subunits of higher-level interactive units, e.g., branches, root – shoot subsystems, or entire plants.

Contrasting response of mountain birch to damage by Eriocrania leafminers in polluted and unpolluted habitats

2005 ◽  
Vol 83 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Mikhail V Kozlov
Keyword(s):  
Fluctuating Asymmetry ◽  
Leaf Size ◽  
Betula Pubescens ◽  
Leaf Damage ◽  
Interactive Effects ◽  
Mountain Birch ◽  
Foliar Damage ◽  
Long Shoots ◽  
Intact Leaves ◽  
Short Shoots

The leafmining larvae of Eriocrania spp. (Lepidoptera, Eriocraniidae) develop in the expanding leaves of mountain birch, Betula pubescens subsp. czerepanovii (Orlova) Hämet-Ahti. The larva usually consumes over a half of the leaf, implying moderate foliar damage to an individual shoot. I demonstrated that in unpolluted forests, effects of damage are restricted to the mined leaf, which grows smaller and demonstrates higher fluctuating asymmetry than intact leaves. In contrast, in heavily polluted industrial barrens, mining of the single leaf adversely affects the entire shoot; timing and expression of responses depend on shoot type. In infested short shoots, intact leaves grow smaller and more asymmetrical than leaves in control shoots, whereas infested long shoots demonstrated no current-year response; this difference suggests that long shoots are more competitive than short shoots and can acquire additional resources to compensate for herbivore damage. In contrast, in the next year after damage, no consequences of mining were detected in short shoots, whereas infested long shoots produced lower numbers of axillary long shoots than controls. The detected interactive effects of pollution and leaf damage most probably result from resource limitation in birches growing on low-nutritive toxic soils.Key words: Betula pubescens subsp. czerepanovii, foliar damage, fluctuating asymmetry, Kola peninsula, leaf size, shoot growth.

scholarly journals Effect of dietary incorporation of fish/prawn meal on performance of Catla catla (Hamilton) during nursery phase

2017 ◽  
Vol 64 (1) ◽  
pp. 44
Author(s):  
Pratap Chandra Das ◽  
Suhas Prakash Kamble ◽  
Kartik Chandra Parida ◽  
Kedar Nath Mohanta
Keyword(s):  
Fish Meal ◽  
Protein Efficiency Ratio ◽  
Specific Growth ◽  
Catla Catla ◽  
Efficiency Ratio ◽  
Groundnut Oil ◽  
Growth And Survival ◽  
Cooking Process ◽  
Final Weight ◽  
Final Length

Nursery evaluation of catla spawn was carried out by feeding three iso-nitrogenous diets (35% protein in raw and cooked form) for a period of 30 days. The three test diets (treatments) in raw form were: T1 - groundnut oil cake (GOC) + rice bran (RB) + vitamin-mineral (V-M) premix; T2 - GOC+RB+fish meal (FM) + V-M premix, T3 - GOC+RB+prawn meal (PM)+V-M premix. The diet groups GT1, GT2 and GT3 respectively were same feed combinations in cooked form. Incorporation of prawn meal as animal protein source led to significantly higher final weight, final length, % weight gain, specific growth rate (SGR) and protein efficiency ratio (PER) compared to diet with and without fish meal incorporation. Whereas, diet containing fish meal improved the fry growth and survival rate only when it was cooked. Cooked diet either with fish or prawn meal incorporation led to better fry growth over the respective non-cooked diets, revealing the advantage of cooking process for better nourishment in catla fry during nursery phase.

scholarly journals Effects of different feed items on the growth and survival of endangered riverine catfish Rita rita (Hamilton)

1970 ◽  
Vol 28 ◽  
pp. 11-14 ◽  
Author(s):  
MR Amin ◽  
MFA Mollah ◽  
MR Ali ◽  
M Nahiduzzaman
Keyword(s):  
Early Morning ◽  
Initial Length ◽  
Growth And Survival ◽  
Growth Performances ◽  
Significant Difference ◽  
Final Weight ◽  
Final Length ◽  
The Mean ◽  
Chicken Viscera ◽  
Formulated Feed

The study was conducted to determine a suitable feed for the desirable growth ofriverine catfish Rita rita (Hamilton) from January 2006 to December 2006. The experiment hadthree treatments with three replicates. Nine chambers of the raceway each of size 1.83 × 1.12 sqmeter were used. Local prawn, chicken viscera and commercially available formulated feed (CP)were supplied in treatment T1, T2 and T3, respectively at the rate of 7% body weight. Feed wassupplied twice in a day in the early morning and in the evening as the fish is nocturnal. The initialaverage weight of fish was 24.93±0.05g, 24.99±0.04g and 24.95±0.04g in T1, T2 and T3,respectively. The final weight of the fish under three treatments was 425.05±1.04g, 425.68±1.05gand 177.61±1.45g respectively. The initial length was 8.48±0.02, 8.49±0.02 and 8.50±0.01 in T1, T2and T3, respectively. The final length was 25.22±0.06 cm, 25.21±0.14 cm and 14.87±0.13 cm in T1,T2 and T3, respectively. The mean final weight and length was significantly (p<0.05) higher in T1and T2 compared with T3. However, there was no significant difference (p>0.05) between T1 and T2in terms of final weight and length was concerned. Better growth performances, however, wereobserved in T2 and T1, where prawn and chicken viscera were supplied as feed respectively.Lowest growth performance was observed in T3 where formulated feed (CP feed) was supplied.Key Words: Riverine Catfish; Feed; Growth; SGR; Survival.DOI: 10.3329/ujzru.v28i0.5279Univ. j. zool. Rajshahi Univ. Vol. 28, 2010 pp. 11-14

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