Argentinian wild diploid Solanum species as sources of quantitative late blight resistance

Greenhouse and field evaluations of quantitative resistance to late blight in genotypes of the wild Argentine diploid species Solanum chacoense, Solanum commersonnii, Solanum microdontum and Solanum maglia were performed with a complex race containing the virulence factors 1, 3, 4, 5, 7,10, 11 of Phytophora infestans and using the percentage of leaf area affected by late blight estimated at weekly intervals. From these readings the area under the disease progress curve (AUDPC) was calculated. Highly resistant and susceptible genotypes were identified. Resistance and variability were found in S. chacoense, which together with S. commersonnii showed a significantly higher level of resistance compared to the susceptible checks. Field evaluations of an F₁ progeny of 165 individuals, obtained from non-inbred diploid parents segregating for foliage quantitative resistance in S. chacoense, were also done by means of AUDPC. The polygenic nature of the resistance and some indication of the presence of both additive and interaction effects were evident. Received: 30 August 1999 / Accepted: 30 December 1999     

Tagging QTLs for late blight resistance and plant maturity from diploid wild relatives in a cultivated potato (Solanum tuberosum) background

Phytophthora infestans causes an economically important disease of potato called late blight. The epidemic is controlled chemically but resistant potatoes can become an environment-friendly and financially justified alternative solution. The use of diploid Solanum tuberosum derived from European tetraploid cultivars enabled the introgression of novel genes encoding foliage resistance and tuber resistance from other species into the modern cultivated potato gene pool. This study evaluated the resistance of the obtained hybrids, its quality, expression in leaflets and tubers and its relation to the length of vegetation period. We also identified genetic loci involved in late blight resistance and the length of vegetation period. A family of 156 individuals segregating for resistance to late blight was assessed by three laboratory methods: detached leaflet, tuber slice and whole tuber test, repeatedly over 5 years. Length of vegetation period was estimated by a field test over 2 years. The phenotypic distributions of all traits were close to normal. Using sequence-specific PCR markers of known chromosomal position on the potato genetic map, six quantitative trait loci (QTLs) for resistance and length of vegetation period were identified. The most significant and robust QTL were located on chromosomes III (explaining 17.3% of variance observed in whole tuber tests), IV (15.5% of variance observed in slice tests), X (15.6% of variance observed in leaflet tests) and V (19.9% of variance observed in length of vegetation period). Genetic characterization of these novel resistance sources can be valuable for potato breeders and the knowledge that the most prominent QTLs for resistance and vegetation period length do not overlap in this material is promising with respect to breeding early potatoes resistant to P. infestans. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

RFLP analysis of the wild potato species,Solanum acaule Bitter (Solanum sect. Petota)

Summary Intraspecific variation of a wild potato species, Solanum acaule Bitt., was analyzed by RFLPs of genomic DNA. One hundred and five accessions were selected throughout the distribution area, including all subspecies, i.e., ssp. albicans (hexaploid), ssp. punae (tetraploid), ssp. acaule (tetraploid) and ssp. aemulans (tetraploid). Twenty-seven low-copy DNA clones (probes) were Southern hybridized with EcoRI, EcoRV, HindIII, and XbaI digests of total DNA of all accessions. In total, 238 RFLPs were detected from 94 enzyme x probe combinations. Among them, 49 RFLPs were specific to ssp. albicans, suggesting that the additional third genome is distinct from its two other genomes. RFLPs between and within subspecies were analyzed by principal component analysis. DNA similarities between subspecies coincided with a former taxonomic treatment in the sense that ssp. albicans is the most distantly related to ssp. acaule and ssp. aemulans is distantly related. Subspecies acaule and ssp. punae were indistinguishable. In addition, RFLPs could be used to distinguish groups within subspecies. Subspecies aemulans, confined to Argentina, was divided into two populations, one from the province of La Rioja and the other from the province of Jujuy. In ssp. acaule, some accessions from the southernmost distribution area were clearly distinguishable, while the others varied continuously, showing a geographical cline from Peru to Argentina.Reference to a specific brand or firm name does not constitute endorsement by the US Department of Agriculture over others of similar nature not mentioned     

Mapping of resistance to the potato cyst nematode Globodera rostochiensis from the wild potato species Solanum vernei

A population of diploid potato (Solanum tuberosum) was used for the genetic analysis and mapping of a locus for resistance to the potato cyst nematode Globodera rostochiensis, introgressed from the wild potato species Solanum vernei. Resistance tests of 108 genotypes of a F₁ population revealed the presence of a single locus with a dominant allele for resistance to G. rostochiensis pathotype Ro1. This locus, designated GroV1, was located on chromosome 5 with RFLP markers. Fine-mapping was performed with RAPD and SCAR markers. The GroV1 locus was found in the same region of the potato genome as the S. tuberosum ssp. andigena H1 nematode resistance locus. Both resistance loci could not excluded to be allelic. The identification of markers flanking the GroV1 locus offers a valuable strategy for marker-assisted selection for introgression of this nematode resistance.Abbreviations BSA bulked segregant analysis - RAPD random-amplified polymorphic DNA - RFLP restriction fragment length polymorphism - SCAR sequence-characterized amplified region     

Characterization and mapping of R Pi-ber , a novel potato late blight resistance gene from Solanum berthaultii

Phytophthora infestans, the causal agent of late blight, threatens potato production worldwide. An important tool in the management of the disease is the use of resistant varieties. Eleven major resistance genes have been identified and introgressed from Solanum demissum. However, new sources of resistance are continually sought. Here, we report the characterization and refined genetic localization of a resistance gene previously identified as Rber in a backcross progeny of Solanum tuberosum and Solanum berthaultii. In order to further characterize Rber, we developed a set of P. infestans isolates capable of identifying each of the 11 R-genes known to confer resistance to late blight in potato. Our results indicate that Rber is a new resistance gene, different from those recognized in S. demissum, and therefore, it has been named R _Pi-ber according to the current system of nomenclature. In order to add new molecular markers around R _Pi-ber , we used a PCR-based mapping technique, named MASP-map, which located R _Pi-ber in a 3.9 cM interval between markers CT240 and TG63 on potato chromosome X. The location of R _Pi-ber coincides with an area involved in resistance to different pathogens of potato and tomato.     

Biological containment of potato (Solanum tuberosum): outcrossing to the related wild species black nightshade (Solanum nigrum) and bittersweet (Solanum dulcamara)

The biological containment of the potato (Solanum tuberosum) was assessed by establishing the crossability of this tuberous crop with the related wild non-tuberous species in The Netherlands, black nightshade (S. nigrum) and bittersweet (S. dulcamara). To circumvent crossability barriers, genotypes with different ploidy number were employed and crosses were performed under different environmental conditions. S. dulcamara was shown to be incongruent with potato at all ploidy levels, while S. nigrum displayed unilateral incompatibility. If S. nigrum was emasculated and used as female, fertilization by potato pollen resulted in berry set and seed development. Emasculation of S. nigrum was essential in this cross, because analysis of the fertilization process demonstrated that this species is highly self-compatible and potato pollen was outcompeted by pollen of S. nigrum. The hybrid seeds derived from this cross did not mature and appeared not to be viable. By application of the technique of embryo rescue of immature embryos, hybrid plants could be obtained. However, these hybrid plants proved to be sterile. These data demonstrate that gene flow by pollen dispersal from potato to its most common wild relatives in Western Europe is highly unlikely. The potato is thus a naturally contained species in this part of the world.     

Mitochondrial DNA variation in cultivated and wild potato species (Solanum spp.).

The European cultivated potato, Solanum tuberosum subsp. tuberosum, has 6 related cultivated species and more than 200 wild relatives. In Solanum spp., studies of cytoplasmic organelles have been mainly confined to the plastid DNA composition of cultivated and wild species. In this study, 53 genotypes of 30 potato species belonging to the subsections Estolonifera and Potatoe, 2 tomato species, and a black nightshade genotype were examined using PCR markers to evaluate mitochondrial DNA diversity and assess whether mtDNA variability was correlated with series classification, geographical origin, ploidy, and endosperm balance number (EBN). The markers used revealed interspecific mtDNA variability in Solanum spp. and identified 13 different haplotypes. Intraspecific variability was also observed in a few species and genomic regions. Cluster analysis allowed arrangement of the 13 haplotypes into 7 subgroups, and statistical association tests showed significant relationships between mitochondrial patterns detected by molecular analysis and ploidy, EBN, and geographical origin. On the whole, the evolutionary patterns for the genomic regions analyzed reflected the species relationships established on the basis of morphological and molecular (nuclear and plastidial DNA) data. The mtDNA variability shown is also important for better characterization of genetic resources for potato breeding.     

The use and limits of AFLP data in the taxonomy of polyploid wild potato species in Solanum series Conicibaccata

Solanum sect. Petota (tuber-bearing wild and cultivated potatoes) are a group of approximately 190 wild species distributed throughout the Americas from the southwestern United States south to Argentina, Chile, and Uruguay. Solanum series Conicibaccata are a group of approximately 40 species within sect. Petota, distributed from central Mexico to central Bolivia, composed of diploids (2n = 2x = 24), tetraploids (2n = 4x = 48) and hexaploids (2n = 6x = 64); the polyploids are thought to be polysomic polyploids. This study initially was designed to address species boundaries of the four Mexican and Central American species of series Conicibaccata with AFLP data with the addition of first germplasm collections of one of these four species, Solanum woodsonii, as a follow-up to prior morphological, chloroplast DNA, and RAPD studies; and additional species of series Conicibaccata from South America. AFLP data from 12 primer combinations (1722 polymorphic bands) are unable to distinguish polyploid species long thought to be distinct. The data suggest a complex reticulate history of the tetraploids or the need for a broad downward reevaluation of the number of species in series Conicibaccata, a trend seen in other series of sect. Petota. Separately, through flow cytometry, we report the first ploidy level of S. woodsonii, as tetraploid (2n = 48). The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.     

Collapse of morphological species in the wild potato Solanum brevicaule complex (Solanaceae: sect. Petota)

The major cultivated potato, Solanum tuberosum, and six other related cultivated species, are hypothesized to have arisen from a group of weedy relatives indigenous to the central Andes of central Peru, Bolivia, and northern Argentina. A major problem hindering investigations of the origins of the cultivated species has been a continuing debate over the species boundaries of their putative progenitors. This study investigated the morphological phenetic species boundaries of these putative progenitors and five cultivated taxa, here collectively referred to as the Solanum brevicaule complex. Two hundred fifteen accessions of 30 taxa in the S. brevicaule complex and 42 accessions of six taxa outside of the complex were assessed for 53 morphological traits in replicate plots in a common garden, resulting in a total of over 81;t3000 data points. Phenetic analyses of these data are unable to support 30 taxa, suggesting instead a single variable complex at best only weakly divided into three widely intergrading sets of populations: (1) Peruvian and geographically adjacent Bolivian accessions (including wild species and all the cultigens), (2) Bolivian and Argentinian accessions and S. verrucosum from Mexico (including only wild species), and (3) the Bolivian and Argentinian wild species S. oplocense. These and other data suggest that Hawkes's 1990 treatment (The Potato: Evolution, Biodiversity, and Genetic Resources, Smithsonian Institute Press, Washington, DC.) of 232 morphological species is an overestimate for sect. Petota.     

Location of resistance factors in the leaves of potato and wild tuber-bearing Solanum species to the aphid Myzus persicae

Analysis of electrically recorded feeding behaviour of aphids was combined with colony‐development tests to search for sources of resistance to Myzus persicae (Sulzer) (Homoptera: Aphididae) in tuber‐bearing Solanum species (Solanaceae), aiming at a reduction of potato leaf roll virus (PLRV) transmission. Twenty genotypes, originating from 14 gene bank accessions, representing 13 wild tuber‐bearing Solanum spp., three Solanum tuberosum L. (potato) cultivars, and one S. tuberosum breeding line, were selected. Colony‐development tests were carried out in no‐choice experiments by placing adult aphids on plants of each genotype and counting numbers of nymphs and adults on young plants after 8 and 15 days, and on flowering plants after 14 and 30 days. Large differences were observed among genotypes: some developed small colonies and others developed large ones. Also, in a few genotypes, resistance in mature plants was different for leaves of different ages; young leaves were resistant to aphids whereas old senescent leaves were susceptible. The electrical penetration graph (DC‐EPG system) technique was used to study aphid feeding behaviour on each Solanum genotype for 6 h. Electrical penetration graph (EPG) results also showed large differences among the genotypes, indicating resistance at the leaf surface and at three different levels of plant tissue (epidermis, mesophyll, and phloem). Therefore, it was concluded that different mechanisms of resistance to M. persicae exist among the genotypes analysed. EPGs recorded from aphids on Solanum berthaultii Hawkes and Solanum tarijense Hawkes with and without glandular trichomes showed that strong surface resistance can bias EPG parameters associated with resistance located in deeper tissues. Experimental evidence is presented that the resistance to aphids in the genotypes with glandular trichomes strongly depends on these morphological structures.     

Somatic hybrids between Solanum brevidens and Solanum tuberosum: Expression of a late blight resistance gene and potato leaf roll resistance

Hexaploid somatic hybrids resulting from mesophyll protoplast fusions between Solanum brevidens Phil., PI 218228, and Solanum tuberosum L., PI 203900 were tested for late blight resistance using two races of Phytophthora infestans Monte., de Bary. The S. tuberosum parent was a late blight differential possessing the R4 gene which confers resistance to race 0. The S. brevidens parent is resistant to potato leaf roll virus. Inoculations with both compatible (race 1.3.4.5) and incompatible (race 0) races of P. infestans clearly demonstrated the expression of the late blight resistance gene in all of the hybrid progeny tested. Most of the hybrids tested were also resistant to potato leaf roll virus (PLRV), indicating that the S. brevidens genes for PLRV resistance were present and expressed.     

Stacking three late blight resistance genes from wild species directly into African highland potato varieties confers complete field resistance to local blight races

Considered responsible for one million deaths in Ireland and widespread famine in the European continent during the 1840s, late blight, caused by Phytophthora infestans, remains the most devastating disease of potato (Solanum tuberosum L.) with about 15%–30% annual yield loss in sub‐Saharan Africa, affecting mainly smallholder farmers. We show here that the transfer of three resistance (R) genes from wild relatives [RB, Rpi‐blb2 from Solanum bulbocastanum and Rpi‐vnt1.1 from S. venturii] into potato provided complete resistance in the field over several seasons. We observed that the stacking of the three R genes produced a high frequency of transgenic events with resistance to late blight. In the field, 13 resistant transgenic events with the 3R‐gene stack from the potato varieties ‘Desiree’ and ‘Victoria’ grew normally without showing pathogen damage and without any fungicide spray, whereas their non‐transgenic equivalent varieties were rapidly killed. Characteristics of the local pathogen population suggest that the resistance to late blight may be long‐lasting because it has low diversity, and essentially consists of the single lineage, 2_A1, which expresses the cognate avirulence effector genes. Yields of two transgenic events from ‘Desiree’ and ‘Victoria’ grown without fungicide to reflect small‐scale farm holders were estimated to be 29 and 45 t/ha respectively. This represents a three to four‐fold increase over the national average. Thus, these late blight resistant potato varieties, which are the farmers’ preferred varieties, could be rapidly adopted and bring significant income to smallholder farmers in sub‐Saharan Africa.     

An ancient R gene from the wild potato species Solanum bulbocastanum confers broad-spectrum resistance to Phytophthora infestans in cultivated potato and tomato

Late blight, caused by the oomycete pathogen Phytophthora infestans, is the most devastating disease for potato cultivation. Here, we describe the positional cloning of the Rpi-blb1 gene from the wild potato species Solanum bulbocastanum known for its high levels of resistance to late blight. The Rpi-blb1 locus, which confers full resistance to complex isolates of P. infestans and for which race specificity has not yet been demonstrated, was mapped in an intraspecific S. bulbocastanum population on chromosome 8, 0.3 cM from marker CT88. Molecular analysis of a bacterial artificial chromosome (BAC) clone spanning the Rpi-blb1 locus identified a cluster of four candidate resistance gene analogues of the coiled coil, nucleotide-binding site, leucine-rich repeat (CC-NBS-LRR) class of plant resistance (R) genes. One of these candidate genes, designated the Rpi-blb1 gene, was able to complement the susceptible phenotype in a S. tuberosum and tomato background, demonstrating the potential of interspecific transfer of broad-spectrum late blight resistance to cultivated Solanaceae from sexually incompatible host species. Paired comparisons of synonymous and non-synonymous nucleotide substitutions between different regions of Rpi-blb1 paralogues revealed high levels of synonymous divergence, also in the LRR region. Although amino acid diversity between Rpi-blb1 homologues is centred on the putative solvent exposed residues of the LRRs, the majority of nucleotide differences in this region have not resulted in an amino acid change, suggesting conservation of function. These data suggest that Rpi-blb1 is relatively old and may be subject to balancing selection.     

Mapping QTLs for resistance to the cyst nematode Globodera pallida derived from the wild potato species Solanum vernei

Resistance to the potato cyst nematode (PCN) species Globodera pallida, derived from the wild diploid potato species Solanum vernei, has been investigated. This source of resistance, which is effective against all of the major pathotypes of G. pallida and Globodera rostochiensis, has been assumed to be due to several genetic factors, but it has proved difficult to deploy effectively in breeding strategies for potato cultivars. Diploid and tetraploid potato populations segregating for 'vernei' resistance were analysed. At the tetraploid level, a bulk segregant analysis (BSA) approach was employed and detected AFLP markers linked to a resistance QTL on potato linkage group V. Conventional linkage analysis of a diploid population identified QTL on linkage groups V and IX. A marker linked to a QTL on linkage group V has been converted to a single-locus PCR-based marker, which can be used to detect the presence of the QTL in diploid and tetraploid potato germplasm. Moreover, there is evidence that one of the AFLPs detected by BSA appears to be specific to an introgressed segment of DNA from S. vernei. These results are compared with those obtained from other studies on resistance to the PCN species G. pallida.     

Allelism of endosperm balance number (EBN) in Solanum acaule Bitt. and other wild potato species

The inheritance of endosperm balance number (EBN), a genetic, dose-dependent crossability system functioning in tuber-bearing Solanum (potato) species, was investigated for certain wild potato species having an EBN equal to one half of their ploidy. The EBN of Solanum acaule, a disomic 4(2EBN) South American species, was investigated by producing F₁ and F₂ hybrids with artificial 4x(2EBN) S. commersonii. This allowed assessment of recombination among the two genomes of disomic S. acaule and that of S. commersonii. When crossability of the hybrids with 1EBN, 2EBN and 4EBN standards was tested, no variation for EBN was detected. The apparent lack of recombination and segregation for EBN in these hybrids indicates that the genomes of S. acaule and S. commersonii carry EBN in a genetically-similar way. Combined with previous reports, these data indicate that the inheritance of EBN is similar in widely-separated taxa from South America and Mexico.     

Reduction of species in the wild potato Solanum section Petota series Longipedicellata: AFLP,RAPD and chloroplast SSR data

Species boundaries were assessed with three molecular markers [AFLPs, RAPDs and chloroplast simple sequence repeats (cpSSRs)] for all six species of wild potatoes (Solanum section Petota) assigned to ser. Longipedicellata: Solanum fendleri, S. hjertingii, S. matehualae, S. papita, S. polytrichon and S. stoloniferum. These tetraploid (2n = 4x = 48) species grow in the southeastern United States (S. fendleri) and Mexico (all six species), and a recent morphological analysis supported only three species: (1) S. polytrichon, (2) S. hjertingii (including S. matehualae) and (3) S. stoloniferum (including S. fendleri and S. papita). We analyzed all six species of ser. Longipedicellata (tetraploid) and also analyzed diploids in ser. Bulbocastana, ser. Pinnatisecta, ser. Polyadenia and ser. Tuberosa; tetraploids in ser. Acaulia and hexaploids in ser. Demissa. Concordant with morphological data, AFLP and RAPD results support the synonymy of S. hjertingii and S. matehualae, and completely intermix S. papita and S. fendleri. However, accessions of S. stoloniferum have a tendency to cluster but with exceptions, and S. polytrichon is completely intermixed with S. fendleri and S. papita. The cpSSRs fail to distinguish any of the species in ser. Longipedicellata. Combined morphological and molecular data support only two species in ser. Longipedicellata: S. hjertingii and S. stoloniferum.     

Solanum mochiquense chromosome IX carries a novel late blight resistance gene Rpi-moc1

Screening of a large number of different diploid Solanum accessions with endosperm balance number (EBN) 1 revealed segregation for strong resistance and sensitivity to Phytophthora infestans in accessions of Solanum mochiquense. Genetic analysis showed that resistance in S. mochiquense accession CGN18263 resides at the distal end of the long arm of chromosome IX, is linked to restriction fragment length polymorphism marker TG328 and is in the neighbourhood of the quantitative trait locus (QTL) Ph-3 conferring resistance to P. infestans in tomato. This is the first genetic study of S. mochiquense, a wild diploid species originating from fog oases in the Peruvian coastal desert.     

The lack of enzymic browning in the wild potato species Solanum hjertingii compared with commercial Solanum tuberosum varieties

Enzymic browning of tuber tissue was evaluated quantitatively for 50 genotypes, representing seven accessions, of Solanum hjertingii, a wild potato species from north-east Mexico, together with five commercial varieties of Solanum tuberosum with a known range of enzymic browning. Ninety-four percent of S. hjertingii clones examined showed less browning than the commercial varieties, with 66% exhibiting half the ‘potential browning’ (a measure of the total enzymic browning resulting from disruption of cellular compartmentalisation in that system) of cv. Maris Piper, a low enzymic browning cultivar. Of these clones, 18 showed no visual discoloration when sliced. Results clearly indicate that the lack of enzymic browning in S. hjertingii is a ‘true’ character. The efficiency of one subjective and two objective methods for obtaining different measures of enzymic browning was assessed. Potential browning of a rehydrated freeze-dried powder was adopted as the most efficient technique for screening enzymic browning.     

Somatic hybrids between Solanum bulbocastanum and potato: a new source of resistance to late blight

 Solanum bulbocastanum, a wild, diploid (2n=2x=24) Mexican species, is highly resistant to Phytophthora infestans, the fungus that causes late blight of potato. However this 1 EBN species is virtually impossible to cross directly with potato. PEG-mediated fusion of leaf cells of S. bulbocastanum PI 245310 and the tetraploid potato line S. tuberosum PI 203900 (2n=4x=48) yielded hexaploid (2n= 6x=72) somatic hybrids that retained the high resistance of the S. bulbocastanum parent. RFLP and RAPD analyses confirmed the hybridity of the materials. Four of the somatic hybrids were crossed with potato cultivars Katahdin or Atlantic. The BC₁ progeny segregated for resistance to the US8 genotype (A-2 mating type) of P. Infestans. Resistant BC₁ lines crossed with susceptible cultivars again yielded populations that segregated for resistance to the fungus. In a 1996 field-plot in Wisconsin, to which no fungicide was applied, two of the BC₁ lines, from two different somatic hybrids, yielded 1.36 and 1.32 kg/plant under a severe late-blight epidemic. In contrast, under these same conditions the cultivar Russet Burbank yielded only 0.86 kg/plant. These results indicate that effective resistance to the late-blight fungus in a sexually incompatible Solanum species can be transferred into potato breeding lines by somatic hybridization and that this resistance can then be further transmitted into potato breeding lines by sexual crossing. Received: 27 October 1997 / Accepted: 11 November 1997     

Evaluation of wild Solanum species for drought resistance: 1. Solanum gandarillasii Cardenas

Since drought is a major factor limiting global potato production, identification of Solanum germplasm with drought resistance features is essential. The current study compared responses of Solanum tuberosum L. ‘Kennebec’ to those of the wild tuber bearing species, Solanum gandarillasii Cardenas, with respect to drought and heat stress. The cultivar Kennebec exhibited more leaf water loss as well as increased osmotic adjustment compared to S. gandarillasii during the imposition of progressively severe drought. In Kennebec, this stress led to severe leaf wilting and eventual canopy loss. However, S. gandarillasii was less sensitive to prolonged drought in terms of reduced loss of above ground biomass. The conservative “water saving” responses of S. gandarillasii included drought sensitive stomata resulting in low transpiration rates. Coupled with this apparent loss of an effective cooling mechanism, S. gandarillasii demonstrated superior thermal tolerance. Decreased intrinsic water use efficiency (WUE) at the leaf level was evident in Kennebec compared to S. gandarillasii when exposed to increasing levels of soil moisture stress and regardless of radiation level. This difference in WUE could be attributed to differences in transpiration rate and not to photosynthetic rate. S. gandarillasii may be appropriate for growth areas exhibiting drought conditions where reduced desiccation and thermal damage to leaf tissues are assets. Kennebec, however, was a ‘water spender’ that would be more appropriately grown under temperate growing conditions with an adequate water supply.