Evaluation of tomato accessions for quantitative and qualitative traits under agro climatic condition of Peshawar

The objective of this research was to screen the tomato accessions for quantative and qualitative traits under agro climatic condition of Peshawar. 17 tomato accessions with a tomato commercial cultivar were evaluated in randomized complete block design with three replication at The University of Agriculture Peshawar, during kharif season 2016. Quantative traits studied were juice pH, total soluble solids, days to flowering, plant height, fruits plant, fruit weight and fruit yield plant. While qualitative traits comprised plant growth type, canopy size, leaf type, flower inflorance, fruit color, fruit shape and fruit firmness. Highly significant differences were observed among tomato accessions for all the quantative traits studied except juice pH. While qualitative traits showed that maximum accessions had indeterminate growth habit (88.9%), Intermediate canopy size (55.6%), curled leaf type (66.7%), medium number of flowers inflorescence (55.6%), red fruit color (61.1%), deep globe fruits (26.7%) and soft fruit firmness (83.3%). Fruit yield plant 1 showed significant positive correlation with juice pH (r=0.580**), TSS (r=0.500**), plant height (r=0.420**), fruits plant (r=0.410**) and fruit weight (r=0.920**) except days to flowering (r=0.310**) which showed significant negative correlation with fruit yield plant. Roma showed highest value of fruit juice pH (4.1), total soluble solids (6.1), fruit weight (54.2 g) and fruit yield plant (688.7 g). Therefor this study suggested that Roma and 31910 could be recommended as commercial cultivars under agro climatic condition of Peshawar and also could be used in future tomato breeding programs.

It is one of the most important crops widely grown in tropical and temperate regions of the world. Tomato have three different types of growth habits namely; determinate, indeterminate and semi determinate [4]. Over the last century, tomato as a major horticultural vegetable crop has attained a tremendous popularity. It can be grown in most places all over the world, like growing in the field, greenhouses and net houses. In Pakistan tomato is grown both as Kharif and Rabi crop on an area of 1689 and 38549 hectares with an average production of 142113 and 423930 tons respectively. The Khyber Pakhtunkhwa (KPK) Province share for Kharif and Rabi crop is 9670 and 3582 hectares with 85754 and 41798 tons production [5]. Tomato is also known as protective food because of its special nutritive values [6]. The tomato fruit is moderately rich in Vitamin A and C and contains 93.8g water, 1.2g protein, 4.8g carbohydrate, 0.5mg carotene [7]. Yellow tomatoes have higher vitamin A content than red tomatoes, but red tomatoes contain lycopene, an anti-oxidant that may contribute to protection against carcinogenic substances. Red color of tomato fruits is the result of chlorophyll degradation as well as synthesis of lycopene and other carotenoids [8].
For sustainable genetic improvement of the crop systematic study and characterization of tomato germplasm is of great importance. For improved breeding program, evaluation is vital in order to know the genetic background and the breeding values of the available tomatoes [9]. Yield components and morphological traits have been widely used in the evaluation of tomato crops. Therefore the current study was conducted to know about the genetic variability of quantitative and qualitative traits in tomato germplasm under agro climatic condition of Peshawar and to select the most promising tomato accessions for future breeding programs.

Materials and methods
The experiment was carried out at The University of Agriculture Peshawar in summer season 2016.17 tomato accessions and a commercial variety were procured from National Agricultural Research Centre (NARC), Islamabad (Table 1). Those seeds were sown in plastic tubes on 17 March, 2016. After a week of seeding those accessions were transplanted to the field using randomized complete block design with three replication. Data were noted on five plants genotype -

Statistical analysis
Quantative traits were subjected to Analysis of variance (ANOVA) according to [11]. Genotypes that showed significant differences were subjected to Least Significant Difference (LSD) test at 5% probability level. Correlation and frequency distribution of qualitative traits were analyzed using statistical package 'STATISTICA-V.8.1.  Results and discussion Tomato juice pH Data regarding total juice pH is presented in (  [12][13][14]. They also reported significant difference for juice pH in tomato genotypes. The juice pH was significantly (P ≤ 0.01) positive correlated with total soluble solids, fruits plant -1 , fruit weight and fruit yield plant -1 , while with plant height it was non-significantly positive correlated. However juice pH had non-significant negative correlation with days to flowering (Table 4). Aoun et al. [15] also found that juice pH was significantly positive correlated with total soluble solids.

Total soluble solids ( 0 Brix)
Statistically analyzed data showed significant differences (P ≤ 0.01) among tomato accessions for total soluble solids. Maximum total soluble solids were recorded for accession 31910 (6) followed by Roma (6), while minimum total soluble solids was recorded for accession 19471 (3.5). These results are strengthened by the findings of Chernet et al. and Parkar and Maleekuu [16,17]. Who also observed significant differences among tomato accessions for total soluble solids. Total soluble solids was significantly (P ≤ 0.01) positive correlated with fruits plant -1 , fruit weight and fruit yield plant -1 . However total soluble solids was significantly (P ≤ 0.01) negative correlated with days to flowering while the said trait was non-significantly positive correlated with plant height (Table 4). Our studied results are in close correspondence with Golani et al. [18]. Who also found positive correlation between TSS and fruit yield.   (Table 4). Izge et al. [22] also found significant positive correlation between plant height and fruit yield plant -1 .  (Table 7). Frequency distribution of fruit color showed the predominance of red color for five genotypes with 27.8%, followed by orange in 11 genotypes (61.1%), pink in one genotype (5.6%) and gold in one genotype (5.6%). Fruit shape of four genotypes (22.2%) was found to be flattened, two genotypes (11.1%) were slightly flattened, three genotypes (16.7%) were globe, five genotypes (27.8%) were deep globe, only one genotype (5.6%) were heart shaped, one were cylindrical (5.6%) and two genotypes (11.1%) were Pyriform. Fruit firmness of 15 genotypes (83.3%) have soft fruit and 3 genotypes (16.7%) had medium fruits firmness. Similar findings were also observed earlier by Grandillo et al. [31]. They also reported significant variation among tomato accessions for qualitative traits.

Conclusions
Analysis of variance showed significant difference among the tomato accession for all the studied traits except juice pH which showed non-significant differences among tomato accessions. Maximum fruit yield plant -1 was recorded for Roma (688.70) followed by accession 31910 (488.20 g). While minimum fruit yield plant -1 was noted for accession 19900 (21.2 g). Qualitative results revealed that maximum accessions have indeterminate growth habit, Intermediate canopy size, curled leaf type, medium number of flowers inflorescence -1 , red fruit color, deep globe fruits and soft fruit firmness. Fruit yield plant -1 showed significant positive correlation with juice pH (r=0.580**), TSS (r=0.500**), plant height (r=0.420**), fruits plant -1 (r=0.410**) and fruit weight (r=0.920**) except days to flowering (r=-0.310**) which showed significant negative correlation with fruit yield plant -1 . Roma performed better followed by accession (31910). Therefor it is suggested that these two tomato genotypes could be used in future tomato breeding programs.

Authors' contributions
Conceived and designed the experiments: N Ara, Performed the experiments: N Samad, Analyzed the data: S Ali, Contributed reagents/ materials/ analysis tools: Manzoor, S Fahad and Q Hussain, Wrote the paper: A Sohail.