As per the pooled data, the study findings showed that the conjugal influences of transplanting window and genotype of tomato had a significant effect on the degree of occurrence of out-break of various diseases and its’ concomitant effects over important yield as we quality parameters of tomato. Data are presented through Fig. 1 to Fig. 8 and the results of the current investigation are addressed below.
Interactive influences of sowing windows and genotypes over the intensity of out-break of tomato yellow leaf curl virus
As far as the interaction of transplanting date and cultivars of tomato is concerned, it could produce statistical variation over degree of occurrence of tomato yellow leaf curl virus [TYCLV] (Fig. − 1). This parameter gave the highest intensity of out-break, when seedling were transplanted on 7th December with respect to variety Local cultivar [S6V10], with a value of 18.69%. This was found as the minimum of 1.06% under combination of commencement of transplanting on 21st October with variety Arka Abhed [S3V1]. In general, acceptably favourable results in this aspect also had been revealed by genotype Arka Abhed, Arka Rakshak and Arka Samrat in combination with sowing windows of 21st September, 7th October, 21st October, 7th November, 21st November and 7th December with having values of 1.08% [S2V1], 1.14% [S4V1], 1.15% [S1V1], 1.19% [S5V1], 1.23% [S6V1], 1.70% [S3V2], 1.72% [S2V2], 1.81% [S4V1], 1.83% [S1V2], 1.91% [S5V2], 1.93% [S6V2] and 1.98% [S3V3], respectively. All these values showed considerable variations from genotypes Local, Chiranjeevi, Arka Abha and Arka Ananya, irrespective of dates of transplanting.
Interactive influences of sowing windows and genotypes over the intensity of out-break of bacterial blight
The intensity of occurrence of bacterial blight of tomato showed significant variations under the conjugal interaction of sowing window (S) and genotype (V) at constant levels of other cultural practices (Fig. − 2). The highest intensity of 10.61% was obtained from the treatment combination S6V10, viz., under the interaction between transplanting on 7th December along with cultivar Local. This was followed very closely by the interactive effect of cultivars Arka Apeksha, Arka Abha, Kashi Amnan, Arka Rakshak and Arka Samrat with same sowing window [i.e., S5V10, S1V10, S4V10, S2V10 and S3V10, respectively] with values of 10.44, 10.21, 10.08, 10.02 and 9.56%, respectively. On the other hand, no sign of out-break of bacterial wilt had been visualized when conjugal influences were judged as date of transplanting on 21st October with all the genotypes, expect those of Local and Chiranjeevi [viz., S3V10 and S3V9, respectively].
Interactive influences of sowing windows and genotypes over the intensity of out-break of early blight
The conjugal effects of date of commence of transplanting and genotype of tomato proved effective to create tangible variations for incidence of occurrence of early blight (Fig. − 3). The maximum intensity for this was found as 5.55% in case of Local cultivar, when it was transplanted on 21st November [viz., S5V10]. Significantly higher incidence of early blight also found as 5.41, 5.32, 5.29, 5.18 and 5.15% with same genotype with sowing windows of 7th December, 21st September, 7th November, 7th October and 21st October [i.e., S6V10, S1V10, S4V10, S2V10 and S3V10, respectively]. All these values showed significant variations from all the other treatment combinations. Commencement of cultivation of tomato genotypes during 21st October, 7th November, 21st October, 21st November and 21st September with accessions namely, Arka Rakshak, Kashi Aman, Arka Samrat, Arka Abhed and Arka Samrat, revealed relatively meagre values for the same as 0.01% [S3V2], 0.01% [S2V2], 0.02% [S4V2], 0.02% [S3V4], 0.02% [S3V1], 0.03% [S3V3], 0.03% [S2V1], 0.03% [S3V3], 0.03% [S2V4], 0.04% [S4V1], 0.04% [S3V5], 0.04% [S1V2], 0.05% [S4V4], and 0.05% [S4V3].
Interactive influences of sowing windows and genotypes over the intensity of out-break of late blight
The highest percentage of occurrence late blight disease of tomato of 6.45 was registered under initiation of transplanting on 7th December as a result of influence of the interaction with genotype Local [i.e. S6V10], followed by 6.31, 6.21, 6.15, 6.14 and 6.10%, respectively found also from genotype Local under transplanting on 21st November, 7th November, 7th October, 21st September and 21st October [viz., S5V10, S4V10, S2V10, S1V10 and S3V10, respectively] (Fig. − 4). Remarkable variations were found for the same with all these treatment combinations from the remaining ones. Practically no symptom of late blight had been visualized with sowing windows of 7th October and 21st October in combination with variety Arka Abhed [i.e., S2V1 and S3V1, respectively]. Equally acceptable results for this parameter also had been seen for the same genotype with sowing windows 21st September [S1V1], 7th November [i.e. S4V1] and 21st November [i.e. S5V1].
In the present investigation the maximum infestation of tomato yellow leaf curl virus (TYCLV), bacterial wilt, early and late blight were visualized as 18.69%, 10.61%, 5.55% and 6.45%, respectively, when transplanting was done as late as on 7th December with conjugal influences of the Local cultivar. As a partial agreement to the aforesaid fact Lukyanenko (1991) has reported that tomato is susceptible to more than 200 diseases and losses of the yield due to the disease was as high as 71–95%. By all, Tobacco mosaic virus (TMV), Tomato leaf curl virus (TLCV) and Tomato yellow leaf curl virus (TYLCV) caused 80, 90 and 100% yield loss of tomato, respectively, as investigated by Martelli and Quacquarelli (1983). The bacterial wilt disease can cause upto 90% yield losses in tomato (Elphinstone, 2005). Keeping near similarity to the current out-comes Mondal et al. (2011) reported the incidence of bacterial wilt disease in tomato, brinjal and potato in West Bengal with 9.86–86.45% damages, respectively. Persistence of high bacterial load within the plant xylem and accumulation of copious number of exo-polysaccharides (EPS) in the xylem is assumed to be the cause of the irreversible wilting of the infected plant culminating in plant death (Hikichi et al., 2017). Environmental factors play a key role in the development of the disease. Early blight develops more rapidly during periods, when environmental conditions alternate between humidity and drought (Parmer et al., 2020). The disease effects on all foliar plant parts and causes a great reduction in quantity (Waals et al., 2001), causing fruit yield losses of up to 86% in India (Datar and Mayee, 1981 and Sahu et al., 2013). Low temperature and high humidity prevailed from November to January favours late blight incidence (Saleem et al., 2016). According to an estimate, 85–90% yield losses recorded in Chittoor District (Ravuri and Kumar, 2018). As per these similar types of earlier research finding and according to the wholesome outcomes of the present study this could be said here that very early (i.e., 21st September) and very late (i.e., 7th December) transplanting mostly might have exerted more conducive atmospheric condition for break out of various diseases of tomato, especially while cultivating with susceptible genotypes.
Interactive influences of sowing windows and genotypes on yield
The concomitant effect of various dates of transplanting and genotypes of tomato in the present investigation exhibited highly considerable variations (Fig. − 5). The highest yield had been found as 66.25 t ha− 1 under 21st October date of planting with variety Arka Apeksha [i.e., S3V5], followed by the Arka Samrat and Arka Abha, with same sowing window [viz., S3V3 and S3V1], where these were obtained as 65.79 and 64.94 t ha− 1, respectively. However, differences between S3V5, S3V3 and S3V1 were insignificant in nature. Genotypes Arka Apeksha, Arka Samrat and Arka Abha also revealed more or less acceptable results with respect to yield of tomato with transplanting on 7th October and 7th November with values of 63.82 t ha− 1 [S2V5], 63.59 t ha− 1 [S2V3], 63.51 t ha− 1 [S4V5] and 63.02 t ha− 1 [S4V3]. Irrespective of genotypes of tomato in majority of the cases commencement on cultivation on 7th December, 21st November and 21st September reduced the yield potentiality in the current study in a considerable manner.
Interactive influences of sowing windows and genotypes on average yield loss on account of diseases incidence
Interactions of transplanting date and genotype of tomato produced significant variation with respect to average yield loss on account of disease incidence (Fig. − 6). The lowest value for this (1.61%) was recorded from variety Arka Abhed, while transplanting was done on 21st October [i.e. S3V1]. Whereas, the maximum average yield loss of 17.96% was found with Local cultivar through 7th December sowing window [S6V10]. Considerably, better result for this also registered during transplanting on 21st October with genotypes Arka Samrat [S3V3], Arka Ananya [S3V7], Arka Abha [S3V8], Arka Rakshak [S3V2] and Kashi Aman [S3V5] with values of 1.81%, 2.04%, 2.27%, 2.27% and 2.57%, respectively. Equally good results in this context, irrespective of cultivars of tomato, used in the present investigation, with respect to average yield loss had been documented with sowing windows such as 21st October [S3], 7th October [S2] and 7th November [S4].
Keeping parity to the intensity of disease outbreak the fruit yield of tomato in the current study showed lower yield potentiality with too early and too late transplanting of seedlings as autumn-winter crop, with proportionate increase in average yield loss percentage. These outcomes showed partial agreement with the previous research studies of Mohanthy (2003), Srivastava et al. (2013) and Shravika et. al. (2020).
Interactive influences of sowing windows and genotypes on lycopene content
Under the influence of interaction of sowing window and cultivar of tomato lycopene content of mature ripe fruit showed statistical variations (Fig. − 7). The highest values for this parameter had been seen under 21st October planting with variety Arka Samrat [i.e., S3V3], with a value of 56.43 mg 100g− 1. In contrast to this, the lowest lycopene content of 14.39 mg 100g− 1 had been registered with treatment combinations S6V10, viz., cultivation of Local cultivar with transplanting at 7th December [i.e., S6V10]. Considerably, better contents of lycopene were also found for the fruits of Arka Samrat and Arka Ananya upon sowing window of 7th October, 7th November and 21st September [viz., S2V3, S4V3, S1V3, S3V7, S5V3 and S2V7, as per the same order], with values for the same as 56.29, 56.07, 55.925, 55.58, 55.45 and 55.28 mg 100g− 1, respectively. Notable fact here is that in the present experiment treatment combinations having inclusion of either Local cultivar [V10] or Arka Alok [V6] or Arka Apeksha [V5] under various dates of transplanting revealed relatively lower contents of lycopene for mature ripe fruits of tomato.
Interactive influences of sowing windows and genotypes on carotenoids content
The specific duration of transplanting in combination with genotype literally produced tangible differences with respect to carotenoids contents of tomato in the present study (Fig. − 8). The highest content of carotenoids of 104.00 mg kg− 1 was obtained from the treatment combination S3V3, viz., under the interaction between transplanting on 21st October along with cultivar Arka Samrat. This was followed very closely by the interaction effect of the same cultivar with sowing windows 7th October, 7th November, 21st September, 21st November and 7th December [viz., S2V3, S4V3, S1V3, S5V3 and S3V3, as per the same order] with values of 99.15, 98.45, 98.23, 96.96 and 94.51 mg 100g− 1, respectively. On the other hand, comparatively lesser carotenoids contents of mature ripe tomato fruits had been visualized, when interactive influences were judged with genotype Local with dates of transplanting as 7th December [S6V10], 21st November [S5V10], 21st September [S1V10], 7th November [S4V10], 7th October [S2V10] and 21st October [S3V10] with values of 18.91, 19.07, 19.27, 19.41, 19.50 and 19.74 mg 100g− 1, respectively.
In majority of the cases in the current investigation better out turn with respect to lycopene and carotenoids contents had been found with variety Arka Abhed, Arka Rakshak and Arka Samrat, with sowing windows between second to third week of October. This might be attributed to the fact that most favorable climatic condition prevailed during these periods for improvement of quality parameters of tomato genotypes. Near similar experimental findings also had been documented by Shi and Le Maguer (2000), according to them the inhibition of lycopene production in tomato took place at higher temperatures (380C). Lycopene constitutes 80–90% of the total carotenoids in tomato fruits (Valverde et al., 2002). So, in the present study the behaviour of fluctuation of carotenoids contents in tomato fruits might be due to the changes in the level of lycopene contents under various experimental conditions. Amrutha and Beena (2020) also observed variations in tomato genotypes for fruit quality parameters at high temperature conditions. Carotenoids and lycopene contents was also observed as low at temperature stress and at control condition (Mamatha et al., 2014).