The occurrence of wild cotton <Emphasis Type="Italic">Gossypium mustelinum</Emphasis> Miers ex Watt populations in the coast of Pernambuco,Northeastern Brazil

In this study, we describe three populations of the wild cotton Gossypium mustelinum Miers ex Watt in the coastal plain to the north of the State of Pernambuco, Northeast Brazil. These populations occur in urban areas in current expansion and under imminent risks of extinction, due to land use changes for house constructions. Distances between these new occurrences and the populations already mapped in the Northeast semiarid Caatinga (Rio Grande do Norte, Ceará, and Bahia) range from approximately 270–950 km. Besides distant, the populations on the coastal plain of Pernambuco also occur in very distinct climatic and edaphic conditions. Aiming at allowing the ex situ conservation of these genetic resources, branches of 66 plants were collected, propagated by the asexual breeding method cutting to regenerate an accession of each plant. These now constitute a germplasm collection in the Department of Agronomy of the Federal Rural University of Pernambuco (UFRPE), in Recife, Pernambuco, Brazil.     

The edible fruit species in Mexico

In Mexico 762 edible fruit species are presently distributed into 288 genera belonging to 87 botanical families. There are 113 cultivated fruit tree species, of which 53 are native and 60 have been introduced; there are also 649 non-cultivated or underutilized species, of which 88 of them were introduced and 554 are native ones. The best representative botanical families are: Anacardiaceae (16 spp.); Anonaceae (19 spp.); Arecaceae (20 spp.); Boraginaceae (10 spp.); Cactaceae (88 spp.); Canabaceae (11 spp.); Caricaceae (9 spp.); Ebenaceae (15 spp.); Ericaceae (22 spp.); Fabaceae (37 spp.); Grossulariaceae (21 spp.); Juglandaceae (15 spp.); Lauraceae (18 spp.); Malpighiaceae (11 spp.); Malvaceae (12 spp.); Melastomataceae (13 spp.); Moraceae (20 spp.); Myrtaceae (29 spp.); Passifloraceae (9 spp.); Pinaceae (12 spp.); Rosaceae (88 spp.); Rubiaceae (9 spp.); Rutaceae (28 spp.); Sapotaceae (24 spp.); Solanaceae (23 spp.); and Vitaceae (24 spp.). This taxonomic richness is related to neartic and neotropical environments, and marked by the human groups present throughout the history of the country. The in situ conservation is recommended in southern, eastern, northeastern and northwestern regions of the country. The ex situ conservation needs consider species with non-orthodox seeds. Probably a few wild edible species need to be grown for commercial cultivation but it is not a rule for all.     

Nitrogen requirements for deficit-irrigated bermudagrass (Cynodon spp.) fairways in South Florida

Several new bermudagrass cultivars are available and commonly used on golf course fairways. However, little is known about their cultural requirements or how these cultivars perform under lower inputs regimes. A 2-year study was conducted at University of Florida, Fort Lauderdale Research and Education Center, to assess performance of four hybrid bermudagrass [Cynodon dactylon L. Pers. X Cynodon transvaalensis (Burtt-Davy)] cultivars (‘Latitude 36’, ‘Tifway 419’, ‘TifGrand’ and ‘TifTuf’), and 2 common bermudagrass (Cynodon dactylon L. Pers.) cultivars (‘Bimini’ and ‘Celebration’) irrigated at either 50% or 80% reference evapotranspiration (ET_o) and fertilised at either 0, 146, 244, or 342 kg N ha⁻¹ year⁻¹. Plots were evaluated monthly for turfgrass quality, dark green colour index (DGCI), normalised difference vegetation index (NDVI), and Chlorophyll Index, and seasonally for N tissue content. Plots watered at 80% ET_o enhanced bermudagrass quality compared to 50% ET_o, DGCI and NDVI only in two months out of 24. Latitude 36 and Celebration were the top-rated cultivars, and their quality was not affected by no N fertilisation. Conversely, TifGrand, TifTuf and Tifway that received no N fertilisation resulted in insufficient quality during the second year of the study. Insufficient quality may be linked to reduced N metabolization compared to the highest rated cultivars. Results show that new cultivars such as Latitude 36 and Bimini could be maintained at sufficient quality levels with reduced water and N inputs in South Florida.     

Soil legacy phosphorus after 10 years of annual dairy liquid manure application in a no-tillage system

The benefits of manure as a source of nutrients for plants and to improve soil quality are well-known. Monitoring of manure application is needed if environmental issues are to be prevented. In particular, the availability and accumulation of phosphorus (P) has to be subject to rigorous monitoring. This study aims to both evaluate the efficacy of the resin method in extracting inorganic labile P in soils under the long-term application of dairy liquid manure (DLM), and verify the influence of DLM on the recovery of applied P and soil legacy P. To realize our objectives, two long-term field experiments were established under a no-tillage system with annual DLM application on sandy clay loam (sandy Oxisol) and clayey (clayey Oxisol) soils. Treatment consisted of DLM applications (0, 60, 120, 180 m³ ha⁻¹ year⁻¹), independent of mineral fertilizer. Soil samples were taken from the 0–5, 5–10 and 10–15 cm layers after 10 years from the beginning of the trial. A single extraction with resin underestimated inorganic labile P; however, successive extractions were able to take up 43% and 26% of the total P in sandy and clayey Oxisols, respectively, whereas in a single extraction the take-up was 17% and 8% from the same soils, respectively. The resin method was more effective in extracting P from the sandy Oxisol. Thus, when interpreting soil P contents for fertilizer planning, the soil texture should be taken into account. DLM application decreased P recovered from applied P, ranging from 54% to 83% (sandy), and 43% to 67% (clayey), and substantially increased soil legacy P.