Differential Responses to Integrated Nutrient Management of Cabbage–Capsicum–Radish Cropping Sequence with Fertilizers and Plant-Growth-Promoting Rhizobacteria

Abstract

The present investigation was carried out to study the differential responses to assimilated nutrient management in the cabbage–capsicum–radish cropping system to develop an integrated plant nutrient supply. The experimental trial was laid out in a randomized complete block design (RCBD) with three replicates and included assimilations of 15 various combinations: T1—recommended dose of fertilizers (RDFs) + farmyard manure (FYM) (Control); T2—nitrogen and phosphorus (NP) + vermicompost (VC) (75% + 2.5 t/ha); T3—NP + VC (50% + 2.5 t/ha); T4—NP + enriched compost (EC) (75% + 2.5 t/ha); T5—NP + EC (50% + 2.5 t/ha); T6—NP + plant-growth-promoting rhizobacteria (PGPR) (75% + 5 kg/ha); T7—NP + PGPR (50% + 5 kg/ha); T8—NP + VC + PGPR (75% + 2.5 t/ha + 5 kg/ha); T9—NP + VC + PGPR (50% + 2.5 t/ha + 5 kg/ha); T10—NP + EC + PGPR (50% + 2.5 t/ha + 5 kg/ha); T11—NP + EC + PGPR (50% + 2.5 t/ha + 5 kg/ha); T12—NP + VC and EC (75% + 2.5 t/ha and 2.5 t/ha); T13—NP + VC and EC (50% + 2.5 t/ha and 2.5 t/ha); T14—NP + VC and EC + PGPR (75% + 2.5 t/ha and 2.5 t/ha + 5 kg/ha); T15—NP + VC and EC + PGPR (50% + 2.5 t/ha and 2.5 t/ha + 5 kg/ha) for two consecutive years. Seedlings of the cabbage cultivar were transplanted with a spacing of 45 × 30 cm, whereas the capsicum seedlings were transplanted with a spacing of 60 × 45 cm. The radish cultivar was sown directly in the field with a spacing of 30 × 7.5 cm. The yield and growth attributes of all three crops were notably impacted by the INM modules. The utilization of a combination of 75% of the recommended quantity of NP + VC and EC, along with PGPR, at a rate of 2.5 t/ha, during cabbage cultivation, led to a noteworthy rise in plant height, equatorial diameter, gross head weight, net head weight, and ultimately, the maximum head yield, as per the statistical analysis. In the case of capsicum, the treatment (T14) module demonstrated superior performance in terms of the major yielding components, namely, fruit size, fruit weight, and number of fruits per plant, resulting in the highest yield compared to the other modules, including RDFs. The cabbage exhibited high protein content and inorganic modules in terms of quality traits, whereas ascorbic acid and total soluble solids (TSSs) levels were high due to strong organic support across all three crops. Thus, it can be inferred that the integrated combination of 75% NP, VC, and EC at 2.5 t/ha, and PGPR, along with the basic application of the full recommended potash and farmyard manure (FYM), led to a reduction of 25% in fertilizers (NP), improved growth and yield, and higher annual net returns. Thus, this incorporation can be suggested as an economically efficient strategy for consistently attaining increased productivity with enhanced excellence.