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Abstract

Tobacco (Nicotiana tabacum L.) plants are known to present high levels of secondary metabolites that increase with the plant age. Molecular biology techniques like restriction enzyme digestion and PCR, requires as pre-requisite the isolation of genomic DNA of suitable purity, good quality and with low levels of contaminants. Several methods to isolate pure and intact tobacco DNA for molecular research purposes have been developed. In this work, a combination between a tobacco seed germination technique using gibberellic acid and a fast and simple genomic DNA extraction method from 14-days old tobacco seedlings to reduce the secondary metabolites levels in the final samples was presented. Ten tobacco genotypes were used to evaluate this method. The DNA concentrations were in a range between 0.73 μg/μL to 1.47 μg/μL for Habana-2000 cv. and Criollo cv., respectively. The absorbance ratios values to determine DNA quality were acceptable. This method allows the obtaining of high molecular weight DNA suitable for digestion with restriction enzymes, EcoRI and BamHI. Tobacco seedlings DNA in a short period of time, in a simple way and with a low cost, was obtained with this extraction method.

Abstract

The body condition scoring system (BCS) is a means of accurately determining body condition of dairy cows, independent of body weight and farm size. The body condition scores represent a subjective visual or tactile (or both) evaluation of the amount of subcutaneous fat in a cow. The system is a useful method of evaluating body energy reserves and is used widely for evaluating nutritional status in dairy cows. The different stages of lactation have different recommended scores. BCS change during the lactation period depends on the milk production, reproduction and health status. Extreme body condition loss in the early lactation can cause irregular heats, longer time to first ovulation, and fail to conceive. The aim of this research was to determine the effect of BCS on Holstein cows’ reproduction. The relationship between some BCS parameters: BCS at calving (BCSc), minimum BCS after calving (BCSmin) and the reduction of BCS after calving (BCSr) on one hand and three reproductive parameters: the days from calving to first service (DFS), number of inseminations to conception (NIC), and days open (DO) on the other hand were studied in three private dairy farms in South Hungary. BCS were determined monthly during milk recording. A total of 786 records of Holstein cows from 1 to 3 lactation were evaluated. DFS was significantly (P<5%) influenced by BCSs and BCSmin. The number of inseminations to conception (NIC) varied according to the individual cow. In the present study was between 1 and 12. The most favourable DO values were observed in the group having >3.5 BCSc (150.04 days), the group with 3.0-3.5 BCSmin (138.92) and the group having >1 BCSr. There was no significant relationship found between DO and the BCS groups.

Abstract

Georgia, the country at the intersection of Europe and Asia, is an important actor on agricultural market, both from Europe and from Asia. The climate of Georgia makes it ideal for growing cereals for animal productions. This climate and the high quality of soil have made the agriculture one of the most important Georgian sectors. The mixed team of researchers from Georgia and Romania has analysed the dynamics of livestock and animal productions in Georgia in order to highlight their future trends and the level of food security in that country.

Abstract

The aim of this study is to be investigated “Yield - irrigation depth” relationship for white breading rose in the conditions of Kazanlak’s Valley (south part of Bulgaria). The field experiment was carried out during 2009 - 2011 period with following variants: 1) without irrigation; 2) irrigation with 50% of the irrigation depth; 3) irrigation with 75% of the irrigation depth; 4) full irrigation (100% of calculated irrigation depth). This relationship is established in two directions - for blossom and for oil, using the degree equation: Yi=1-(1-Yd)x(1-xi)n, (where Yi is the yield by irrigation depth xi, Yd - yield without irrigation, xi - relative irrigation depth and n - exponent). The results show that used equation presents very accurately the change of the yield depending on level of the irrigation depth. The value of “n” is from 1.0 to 1.2 and R>0.94. There is linear relationship (by R2>0.8), which allows predicting the yield of oil by data for yield of blossom.