Perennial fruits crops by the virtue of their nutritional qualities have already emerged as a major alternative, cutting short the menacing load on the consumption of traditional monotonous cereal/tuber crop-based diet. A nutrient management-based production system of perennial fruit crops is inherently complex to understand due to large variation in nutrient use efficiency (NUE). The current state of diagnosis of nutrient constraints in the current season-standing crop has minimum efficacy. Therefore, the development of production-linked nutrient norms using crop-specific index plant parts needs a thorough revisit at the orchard level using conventional basin irrigation versus fertigation. The application of hyperspectral analysis as proximal sensing of nutrient stress has started imparting precision to nutrient constraint diagnosis. On the other hand, the biggest constraint in making soil test ratings more purposeful is the non-redressal of spatial variation in soil fertility in the form of soil fertility analogs vis-a-vis fruit crops. The conjoint use of geoinformatics and Nutrient Experts as decision support tool(s) accommodating site-specific nutrient management strategy, newer concept of fertigation such as open-field hydroponics and variable-rate application as possible improvements in NUE collectively using a logical relationship between canopy volume and nutrient requirement, and exploiting further the nutrient–harmone and nutrient–microbe (in the consortium mode) synergies have yielded a definite edge over conventional methods of nutrient management options in fruit crops.

Fruit crops offer a strong sink for sequestration of atmospheric carbon dioxide, thereby, aid in moderating the impact of climate change-related issues, besides creating a parallel nutrient sink. Mere annual application of organic manures/composts has failed to address different soil fertility functions due to failure to prolong the impact of soil organic pool on long-term basis. The paradigm shifts from purely inorganic to either organic fertilizers or in combination with chemical fertilizers and microbial inoculants (preferably in consortium mode) started gaining wide scale use for enhanced soil health vis-à-vis elevated quality production and reduced rhizosphere CO₂ emmission. This change of concept later formed the basis for Integrated Soil Fertility Management (ISFM)-based strategy involving three basic components viz., microbial inoculants (biofertilizers), inorganic fertilizers, and organic fertilizers. Development of microbial consortium exploiting the microbial synergisms with variety of fruit crops as an important component of ISFM is one of the popular methods of managing multiple soil fertility constraints occurring within the rhizosphere. Further advancements in rhizosphere-specific consortia (often by scaling up crop-microbiome) mediated ISFM could further fulfil the nutrient demand and supply by crop. Upscaling such studies through rhizosphere hybridization has provided some initial inroads in harnessing the potential of different rhizosphere microbial communities. ISFM studies carried out in fruit crops in India, Iran, and China showed better agronomic response and soil health-related properties, considered very close to climate-resilient soil fertility management, a gateway to sustainable quality production. The review also highlights the future directions for ISFM in fruit crops catering to their multiple requirements.

Sustainable agriculture has been consistently challenged due to the menace of changing climate, thereby, causing depletion in carrying capacity of soil vis-à-vis agronomic response of crop. Of late, biochar has turned out to be the most promising option to address these issues. The present review takes stock of the research work accrued under varied agro-pedological conditions, highlighting the response of biochar in a soil-plant-environment continuum. The properties of biochar depended hugely on the source of feedstock and pyrolysis conditions, with its uniqueness resting with high specific surface area and stable carbon source, pre-disposing to better soil health associated crop responses. However, the current biochar recommendations for different crops are high, unless evaluated in combination with fertilizers or organic manures to address both short-term and long-term benefits through soil carbon mediated nutrient supply chain for sustainable crop performance. The role of biochar in scavenging the soil pollutants and pesticide residues, and reducing the emission of greenhouse gases has perched this carbon source with an added advantage over other conventionally used carbon sources. Authors have put forward future issues with an emphasis on the development of crop-based value-chain management of biochar.

Fruits crops by the virtue of their nutritional qualities have already emerged as a major alternative, cutting short the menacing load on the consumption of traditional monotonous cereal/tuber crop-based diet. Huge microbial diversity has displayed different magnitude of synergism with fruit crops, which played a catalytic role in unlocking the productivity stagnation through improved efficacy of applied nutrients. Perennial fruit crops are better equipped to be benefitted through nutrient-microbe synergy because of their perennial framework and root configuration. However, use of multiple inoculation through crop specific microbial consortium, especially AM-based consortium in combination with nutrients (organic or inorganic in nature) provided a much better option in fruits with an added element of much better labile pool of microbial (taxonomic, function, and metabolic diversity) and nutrient pool of the rhizosphere for stronger soil carbon sink ultimately. The concept of “rhizosphere hybridization” is, therefore, advocated to harness the value added benefit of nutrient -microbe synergy, besides providing dynamism to microbial consortium suiting to wide range of perennial fruits. Microbial consortium augers well, with fertigation option as well, as a pretreatment of soil before injecting soluble mineral fertilizers into the wetting zone of drippers in order to improve upon the fertilizer use efficiency.

Microorganisms have dynamic and complex interactions with their hosts. Diverse microbial communities residing near, on, and within the plants, called phytobiome, are an essential part of plant health and productivity. Exploiting citrus-associated microbiomes represents a scientific approach toward sustained and environment-friendly module of citrus production, though periodically exposed to several threats, with Huanglongbing (HLB) predominantly being most influential. Exploring the composition and function of the citrus microbiome, and possible microbial redesigning under HLB disease pressure has sparked renewed interest in recent times. A concise account of various achievements in understanding the citrus-associated microbiome, in various niche environments viz., rhizosphere, phyllosphere, endosphere, and core microbiota alongside their functional attributes has been thoroughly reviewed and presented. Efforts were also made to analyze the actual role of the citrus microbiome in soil fertility and resilience, interaction with and suppression of invading pathogens along with native microbial communities and their consequences thereupon. Despite the desired potential of the citrus microbiota to counter different pathogenic diseases, utilizing the citrus microbiome for beneficial applications at the field level is yet to be translated as a commercial product. We anticipate that advancement in multiomics technologies, high-throughput sequencing and culturing, genome editing tools, artificial intelligence, and microbial consortia will provide some exciting avenues for citrus microbiome research and microbial manipulation to improve the health and productivity of citrus plants.

Walnut (Juglans regia) is an important nut tree species in the world, whereas walnut trees often face inadequate phosphorus (P) levels of soil, negatively limiting its growth and yield. Arbuscular mycorrhizal fungi (AMF) can colonize walnut roots, but whether and how AMF promotes walnut growth, physiological activities, and P acquisition is unclear. The present study aimed to evaluate the effects of Diversispora spurca on plant growth, chlorophyll component concentrations, leaf gas exchange, sugar and P concentrations, and expression of purple acid phosphatase (PAP) and phosphate transporter (PT) genes in leaves of J. regia var. Liaohe 1 seedling under moderate (100 μmol/L P) and low P (1 μmol/L P) levels conditions. Three months after inoculation, the root mycorrhizal colonization rate and soil hyphal length were 45.6−53.2% and 18.7−39.9 cm/g soil, respectively, and low P treatment significantly increased both root mycorrhizal colonization rate and soil hyphal length. Low P levels inhibited plant growth (height, stem diameter, and total biomass) and leaf gas exchange (photosynthetic rate, transpiration rate and stomatal conductance), while AMF colonization significantly increased these variables at moderate and low P levels. Low P treatment limited the level of chlorophyll a, but AMF colonization did not significantly affect the level of chlorophyll components, independent on soil P levels. AMF colonization also increased leaf glucose at appropriate P levels and leaf fructose at low P levels than non-AMF treatment. AMF colonization significantly increased leaf P concentration by 21.0−26.2% than non-AMF colonization at low and moderate P levels. Low P treatment reduced the expression of leaf JrPAP10, JrPAP12, and JrPT3;2 in the inoculated plants, whereas AMF colonization up-regulated the expression of leaf JrPAP10, JrPAP12, and JrPT3;2 at moderate P levels, although AMF did not significantly alter the expression of JrPAPs and JrPTs at low P levels. It is concluded that AMF improved plant growth, leaf gas exchange, and P acquisition of walnut seedlings at different P levels, where mycorrhizal promotion of P acquisition was dominated by direct mycorrhizal involvement in P uptake at low P levels, while up-regulation of host PAPs and PTs expressions at moderate P levels.