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SUMMARYEnset [Ensete ventricosum (Welw.) Cheesman (Musaceae)] is a multi-purpose and drought-tolerant crop, traditionally grown in Ethiopia. Food from enset has nutritive values similar to potato; it could improve food and livelihood security for many in larger geographical areas. Agronomical advice is needed which requires increased knowledge of management techniques. The purposes of this study were to (i) compare traditional corm pre-treatments when planting for sucker production, (ii) compare all six officially released cultivars regarding sprouting and (iii) investigate the effect of watering on newly buried corms. Emergence rate and number and characteristics of sprouts were recorded. Corms, from 63 two year old plants, were buried in local soil supplied with cow manure in Wolaita Sodo, Ethiopia. Emergence was recorded daily. After nine months, including one rainy season, all suckers (totally 4405) were harvested and individually recorded. Regardless of cultivar, minimum time to emergence was 50 days. Sprouts from split parent corms emerged earlier than from entire. Emergence occurred from 100% of corms, number of sprouts was strongly correlated to cultivar: average 28–106. The cultivars responded similarly to corm splitting: the more pieces the corm was split into, the more sprouts per parent corm. Average pseudostem diameter of the seven largest per parent corm: 8–10 cm for all cultivars, leaf length: 3.1–3.7 m, remaining 2700 smaller suckers: diameter 3 cm (SD 1.8). Watering decreased the average time to emergence and levelled out the differences between pre-treatments. The traditional belief is that watering as well as manure on corm cause rotting; manure is therefore usually put on the soil surface. On the contrary, full emergence and unexpected large suckers may be a result of careful soil preparation with manure applied on corm directly; watering resulted in an even emergence and growth. In conclusion, vegetative propagation of enset is efficient, but methods used and agronomical advice can be improved.

Summary Mechanical control of Tussilago farfara is carried out mainly by soil cultivation. The aim is to deplete the energy stored in the rhizomes. The treatment includes cutting the rhizomes, to stimulate increased shooting, followed by renewed soil cultivation to destroy the shoots and incorporate them into the soil. Factors generally regarded as important in the control of perennial weeds are extent of fragmentation and burial depth. In this study, the importance of these two factors on T. farfara emergence was studied in detail in two pot experiments. Rhizomes were cut into different lengths (5–25 cm) and buried at various depths (1–42 cm) in pots filled with peat soil or clay loam. Shoot germination, emergence and early plant performance were studied. Intensive fragmentation and deep burial (possible to achieve using conventional tillage) are not enough to completely hinder emergence of T. farfara; 6‐cm fragments emerged and developed normal leaves from 42 cm depth, regardless of soil type. However, there were higher total emergence and emergence rates in peat soil than in clay soil. Burial depth was correlated with time to emergence; burying rhizome fragments, not longer than 25 cm, to at least 20 cm depth gave a time to emergence of at least 20 days. The delay of weed emergence should allow good establishment of a crop and ensure a significant competitive effect against T. farfara.

Dalbato A.L., Kobza F., Karlsson L.M., 2013. Eff ect of polyploidy and pollination methods on capsule and seed set of pansies (Viola × wittrockiana Gams). Hort. Sci. (Prague), 40: 22-30.Pansy, Viola × wittrockiana, is a popular ornamental plant. Eff ects of polyploidy on phenotype and four pollination methods on capsule and seed set were studied using ten octoploid (2n = 8x) and two hexadecaploid (2n = 16x) genotypes, originating from induced mutagenesis. Principal component analysis, using 19 phenotypic, phenological and physiological characteristics, revealed that hexadecaploids showed larger diff erences to the corresponding standard cultivars than octoploids. Number of seed per capsule was similar among genotypes. Capsule set with open pollination was 32-64 %, with self-pollination by hand 18-49% and with cross-pollination by hand 14-43%, while no plant successfully set capsules with seeds under isolators if not pollinated manually. Th us, Viola × wittrockiana is self-compatible but requires an agent-mediation for successful pollination. Th e induced phenotypes were found stable over four generations. Hexadecaploids had more attractive phenotypes but fewer seeds than octoploids. However, variation in seed set enabled selection of plants with high fertility, and average seed set increased over generations. Th us, new varieties, fulfi lling aesthetic criteria as well as economic and agronomic traits, can be bred from induced mutagenesis. Pansies (Viola × wittrockiana Gams) are popular bedding plants. Whilst perennial by nature they are usually grown as an annual or biennial in garden beds, pots, borders, in hanging baskets or in landscapes (Horn 1996;Bailey 1998). Th ere is a seemingly unlimited need for new varieties. Th e planned pansy breeding through purposeful hybridization began in 1862 (Horn 1956). Breeding goals focused on selecting plants for unusual fl ower colours and increased fl ower size from the initial cross made between the small fl owered heartsease (V. tricolor L.) and yellow large fl owered V. lutea Huds. (Wittrock 1895). Hybridization between an alpine perennial, V. cornuta L., and V. altaica (Ker-Gwal) Pall. -a perennial with large and varied fl ower colours gave hundreds of pansy cultivars (Wittrock 1895;Horn 1956). Garden pansy (V. × wittrockiana Gams) is an octoploid (n = 6, 8x = 48) which is thought to be derived from cross combinations among V. tricolor (2n = 26), V. lutea (2n = 48), V. cornuta (2n = 22) and V. altaica (Clausen 1927;Horn 1956;Yockteng et al. 2003). Garden pansy is larger than its ancestors in plant height and fl ower size (Wittrock 1895).