Florida Citrus Nursery Trends and Strategies to Enhance Production of Field-Transplant Ready Citrus Plants

Tripti Vashisth,Changpin Chun,Monica Ozores Hampton

doi:10.3390/horticulturae6010008

Abstract

The Florida citrus industry is going through major changes and considerable replanting. Many growers are planting varieties, especially rootstocks, that are potentially productive under Huanglongbing (HLB; Candidatus Liberibacter asiaticus) prevalent conditions. However, the high demand for new plant material has put tremendous pressure on citrus nurseries and has created a bottleneck in production. Often it can take more than one year to produce field-transplant ready plants in nurseries; therefore, there is a critical need to accelerate plant production. This three-part study was conducted with the following objectives: (1) determine citrus nursery trends; (2) evaluate use of compost for rootstock germination; and, (3) evaluate use of compost for rootstock seedling growth. According to the nursery survey, rootstock seed germination and seedling growth were the most time-consuming, taking 6–8 months. Moreover, it was apparent from the survey results that 44% of the citrus nurseries were experimenting with potting mixes to achieve adequate plant growth and quality. Our greenhouse study demonstrated successful use of yard waste compost in place of peat moss in a potting mix. With use of 37% to 50% of compost in the potting mix, the overall germination rate and mean emergence time were improved to 70% in less than four weeks for US-897 rootstock as compared to no compost in the potting mix. In addition, 37% to 50% compost resulted in higher biomass accumulation in seedlings. When seedlings of rootstocks C-32 and Flying Dragon were grown with 37% to 50% compost, the growth rate and, therefore, percentage of successful budding were significantly increased as compared to no compost. In addition, substrate analysis indicated that a high compost potting media was rich in mineral nutrients, hence the use of fertilizer in nurseries could be minimized. Altogether, use of compost in place of peat moss seems promising and could accelerate germination and growth of rootstocks, reducing the production time as well as cost.

Highlights

Citrus is one of the largest and most important fruit crops grown in 135 countries and regions around the world
Our results indicated that yard compost may have more beneficial properties compared to sugarcane compost; compost can be successfully used to substitute for peat moss in the potting mix, thereby providing an environmentally and economically friendly alternative
We propose that a high nutrient profile, especially of nitrogen (Table 2) [25,29,31,32,33], in high compost treatments resulted in enhanced growth

Summary

Introduction

Citrus is one of the largest and most important fruit crops grown in 135 countries and regions around the world. Citrus plants grown commercially are composed of rootstock and scion varieties, and the rootstocks have a great impact on scion growth [1], nutrition [2], fruit size, yield and quality [1,3] as well as to tolerance to biotic and abiotic stresses [4,5]. Most of the commercially used citrus rootstocks produce nucellar embryos [6,7], allowing the use of seeds for rootstock propagation. Many growers are relying on good nutritional care of trees [11,12]. There are some newly introduced citrus rootstocks that exhibit

Methods

Results

Conclusion