The spiny leaved Vitis. Here is what it looks like: If anyone knows of a seed source, please let me know.

These abstracts may be informative. CYTOGENETIC STUDY OF INTERSPECIFIC HYBRIDS BETWEEN VIRIS ROTUNDIFOLIA AND VITIS VINIFERA Authors: X. Xu, J. Lu Muscadine grape (Vitis rotundifolia Michx.) has a chromosome number of 2n = 40. European bunch grape (Vitis vinifera L.) has a chromosome number 2n = 38. With few exceptions, the chromosome number of hybrids between V. rotundifolia and V. vinifera is 2n = 39. As a result, the hybrids are either completely sterile or highly sterile with some fertility. To understand the variation of hybrid fertility, a study was conducted to investigate the chromosome number and pairings of the interspecific hybrids Jumbo (V. rotundifolia) x ÂThompson Seedless (V. vinifera) in mitosis and meiosis. Interspecific hybrids were obtained from crosses of muscadine grape (female) x V. vinifera (male) and from reciprocal crosses. Chromosome numbers of the hybrids used for this investigation were first confirmed by root tip cells (RTC) in mitosis. Most of them had a chromosome number 2n = 39. Several morphological characteristics also clearly indicated that they are true hybrids of V. rotundifolia x V. vinifera. Microscopy studies at meiosis of pollen mother cells (PMCs) showed a certain degree of chromosome pairing (bivalent) with some multivalent and monovalents. For those hybrids with 2n = 39, chromosome pairs ranged from 13 to 19. The result indicated that the low fertility of the hybrids is mainly due to the lack of chromosome pairings in their meiosis. A GENETIC MAP OF VITIS RUPESTRIS X MUSCADINIA ROTUNDIFOLIA LOCATING RESISTANCE TO XIPHINEMA INDEX, THE DAGGER NEMATODE Michaeleen Callahan , Yimin Jin , Fangyou Gao , Andrew Walker Muscadinia rotundifolia has very strong resistance to a wide range of grape pests. Although this species is generally incompatible with Vitis species, it does make fertile hybrids with V. rupestris. These hybrids form a unique genetic bridge allowing introgression of resistance genes into cultivated grape. Genetic linkage maps of two V. rupestris "A. de Serres" (2n=38) X M. rotundifolia "Cowart" (2n=40) hybrids were constructed using the pseudotestcross strategy. Four hundred eighteen AFLP markers, 32 ISSR markers, 23 RAPD markers, and 18 microsatellites were used in the maps. Markers segregating 1:1 (316) were used to construct framework maps by comparing results from PGRI, MAPMAKER 3.0, and JoinMap 3.0. Each map contained 19 linkage groups (LOD > 4.0) covering 806 cM and 902 cM for the paternal and maternal parents respectively. One hundred seventy-three markers segregating 3:1 were used to align homeologous linkage groups between the maps. Genome length and map coverage will be presented. A locus associated with resistance to Xiphinema index, the dagger nematode vector of grapevine fanleaf virus, was also positioned on the map. "Muscadine grapes (Vitis rotundifolia) Subgenus Muscadinia has 2n=40 chromosomes compared to 2n=38 for bunch grapes Very resistant to common grape diseases Do not cross readily with bunch grapes Unique flavor and texture" from http://www.hort.purdue.edu/hort/courses/HORT414/Grapelecture.html "Dunstan developed a number of Vitis x Muscadinia hybrids that were backcrossed to interspecific Vitis hybrids. The offspring from these difficult to accomplish crosses have many characteristics of both parents and restored fertility (often lost in Vitis x Muscadinia hybrids). " from http://www.ars-grin.gov/npgs/cgc_reports/grapecgc2001.htm These references: Lu, J., Prins, B. Interspecific hybridization between Euvitis and Muscadinia grape species. (2000). Hortscience 35: 501. Lu, J., Schell, L. Intersubgeneric hybridization between Muscadinia and Euvitis species. (1998). Hortscience 33: 516. Lu, J., Schell, L. Introgressing seedlessness from Vitis vinifera into Vitis rotundifolia. (1999). Hortscience, pp. 523-524. Lu, J., Schell, L., Ramming, D. W. Interspecific hybridization between Vitis rotundifolia and Vitis vinifera and evaluation of the hybrids. (2000). Acta Horticulturae 528: 479-486.

Am looking for a seed source of the Asiatic Subtropical Vitis Davidii. Here is a link that might be useful:

Still am looking for a seed source for this vine. I planted a pkt. a year ago, but none came up. Maybe was old seed?