Dwarfing of Breadfruit (Artocarpus altilis) Trees: Opportunities and Challenges

Abstract

Breadfruit [Artocarpus altilis (Parkinson) Fosberg)] is a traditional staple crop grown for its starchy fruit throughout the tropics. It has long been recognized for its potential to alleviate hunger in the region. However, being a tree of 10 -30m, breadfruit is vulnerable to wind damage. Owing to the continuing trend of global climate change, the success of the species as a sustainable crop for delivering local food security is compromised by the likelihood of more intense tropical windstorms in the island nations. Tree height also forms a major constraint to disease management and fruit harvesting. These imperatives have driven an increasing interest in developing breadfruit varieties with short stature. While a great diversity of breadfruit cultivars with varying nutritional and agronomic characteristics exists, the genetic resource showing dwarfing traits is largely uncharacterised. Historically, there has been no intentional breeding for breadfruit cultivars. The long growth cycle, predominantly vegetative propagation and lack of genome information create challenge for crop improvement through traditional breeding. In this review, we highlight the current knowledge of plant dwarfism and its application in agricultural practices and genetic improvement for dwarf phenotype, and present options and tools for breadfruit dwarfing with special reference to natural genetic variability for dwarfing rootstocks, plant growth regulators, potential of mutagenesis and its combination with the currently Review Article

A Dwarf Phenotype Identified in Breadfruit (Artocarpus altilis) Plants Growing on Marang (A. odoratissimus) Rootstocks

“…Significant tree loss, due to intense tropical windstorm has driven an interest in the development of dwarf phenotype in breadfruit [2,3]. Small tree size is also increasingly sought for the transition toward high-density planting to maximize fruit production, and reducing the cost of management, such as pruning and harvesting [4]. Breadfruit has hundreds of cultivars with great diversity in morphological and agronomic characteristics [1,5,6], but the dwarf variety of the species has not been reported.…”

Plasma membrane H+‐ATPase activity and graft success of breadfruit (Artocarpus altilis) onto interspecific rootstocks of marang (A. odoratissimus) and pedalai (A. sericicarpus)

“…The microsomal fraction were prepared at 4 °C as previously described (Zhou et al . ,). Briefly, tissues (leaves or stems of ~50 g) were homogenised in ice‐cold medium: 1:3 w/v; 0.1 m Tris‐Mes pH 7.7 with 2 m m dithiothreitol (DTT), 20 m m ethylene diamine tetraacetic acid (EDTA), 20 m m ethylene glycol bis (2‐aminoethyl) tetraacetic acid (EGTA), 0.5 m sucrose, 10 mm ascorbic acid, 1 m m phenylmethylsulfonyl fluoride (PMSF) and 2% (w/v) insoluble polyvinylpyrrolidone (PVP).…”

“…; Roberts‐Nkrumah ; Zhou et al . ). Dwarfism has been achieved through the widespread use of dwarfing rootstocks in many other fruit tree species; however, a dwarfing rootstock for breadfruit has not been investigated.…”

Unlocking the inherent potential of plant genetic resources: food security and climate adaptation strategy in Fiji and the Pacific

“…Another aspect is the high dependence of Pacific Islands on food imports which threatens food and nutritional security (McGregor et al 2009 ). However, in the next fifty years it is anticipated that rising cost of fuel required for the distribution of imported food to remote areas and erratic nature of supplies due to climate change may compel a shift towards local food production systems which are also resilient to climate change (Mertz et al 2012 ; Zhou et al 2014 ). An interesting scenario has been observed in Bellona, Solomon Islands, where due to the erratic nature of external food supplies and frequent breakdown of ships, traditional farming systems emerged as an important source of local food for the people (Mertz et al 2012 ).…”