Question: Charles Knight, a doctor and a botanist in New Zealand, may have studied which grass or forage crop that also serves as the namesake for the town of his birth in England?

Context paragraphs:
Charles Knight (doctor): Charles Knight ( 1808 – 3 September 1891) was a New Zealand doctor, public servant and botanist.  He was born in Rye, Sussex, England in 1808.  Knight was the country's inaugural auditor-general.  In New Zealand, he first lived in Auckland and when the government moved to Wellington, he also relocated to the new capital.  He died at his home in Wellington and is buried at Bolton Street Memorial Park.

Alfalfa: Alfalfa , Medicago sativa also called lucerne, is a perennial flowering plant in the pea family Fabaceae cultivated as an important forage crop in many countries around the world.  It is used for grazing, hay, and silage, as well as a green manure and cover crop.  The name alfalfa is used in North America.  The name lucerne is the more commonly used name in the United Kingdom, South Africa, Australia, and New Zealand.  The plant superficially resembles clover (a cousin in the same family), especially while young, when trifoliate leaves comprising round leaflets predominate.  Later in maturity, leaflets are elongated.  It has clusters of small purple flowers followed by fruits spiralled in 2 to 3 turns containing 10–20 seeds.  Alfalfa is native to warmer temperate climates.  It has been cultivated as livestock fodder since at least the era of the ancient Greeks and Romans.  Alfalfa sprouts are a common ingredient in dishes made in South Indian cuisine.

Tourism in New Zealand: Tourism is an important industry in New Zealand, directly contributing NZ$7.3 billion (or 3.7%) of the country's GDP in 2013, as well as directly supporting 110,800 full-time equivalent jobs (nearly 6% of New Zealand's workforce).  A further 5% of GDP (or NZ$9.8 billion) is indirectly contributed through the flow-on effects of tourism.  International tourist spending accounted for 16% of New Zealand's export earnings (nearly NZ$10 billion).  International and domestic tourism contributes, in total, NZ$24 billion to New Zealand's economy every year.  Currently the Deputy Prime Minister of New Zealand Paula Bennett also serves as Minister of Tourism.

Lolium rigidum: Lolium rigidum is a species of annual grass.  Common names by which it is known include annual ryegrass, a name also given to Italian ryegrass ("Lolium multiflorum"), rigid ryegrass, stiff darnel, Swiss ryegrass and Wimmera ryegrass.  It is a native of southern Europe, northern Africa, the Middle East and the Indian subcontinent and is grown as a forage crop, particularly in Australia.

Arthur Bell (engineer): Arthur Wilbraham Dillon Bell (4 April 1856 – 29 May 1943) was an engineer active in New Zealand and Western Australia.  Bell was a son of Francis Dillon Bell; his father was at the time of his birth a member of the New Zealand House of Representatives.  His elder brother, Francis Bell, would later be Prime Minister of New Zealand.  Bell received his secondary schooling in New Zealand and after a time in journalism and as a public servant, he went to England to train as an engineer.  After a short period of engineering work in England, he returned to New Zealand in 1879, and in 1891 he went to Western Australia.  He retired young in 1907 and returned to live in New Zealand.  In 1917, the Bells moved to Melbourne to be with their daughter's family.

Trifolium repens: Trifolium repens, the white clover (also known as Dutch clover, Ladino clover, or Ladino), is a herbaceous perennial plant in the bean family Fabaceae (Previously referred to as Leguminosae).  It is native to Europe and central Asia.  One of the most widely cultivated types of clover, it has been widely introduced worldwide as a forage crop, and is now also common in most grassy areas (lawns and gardens) of North America and New Zealand.  The species includes varieties often classed as small, intermediate and large, according to height, which reflects petiole length.  The term “white clover” is applied to the species in general, “Dutch clover” is often applied to intermediate varieties (but sometimes to smaller varieties), and “ladino clover” is applied to large varieties.

Charles Knight (filmmaker): Charles Knight (nicknamed "Tankboy") is a New Zealand filmmaker.

Festuca pratensis: Festuca pratensis, the meadow fescue, ( syn.  "Bromus pratensis" (Huds. ) Spreng. , "Bucetum pratense" (Huds. ) Parn. , "Festuca fluitans" L. var.  "pratensis" (Huds. ) Huds. , "Festuca elatior" L. subsp.  "pratensis" (Huds. ) Hack. , "Lolium pratense" (Huds. ) Darbysh. , "Tragus pratensis" (Huds. ) Panz.  ex B.D.Jacks. , and "Schedonorus pratensis" (Huds. ) P.Beauv. ) is a perennial species of grass, which is often used as an ornamental grass in gardens, and is also an important forage crop.

Rye: Rye ("Secale cereale") is a grass grown extensively as a grain, a cover crop and a forage crop.  It is a member of the wheat tribe (Triticeae) and is closely related to barley (genus "Hordeum") and wheat ("Triticum").  Rye grain is used for flour, rye bread, rye beer, crisp bread, some whiskeys, some vodkas, and animal fodder.  It can also be eaten whole, either as boiled rye berries or by being rolled, similar to rolled oats.

Eric Godley: Eric John Godley (10 May 1919 – 27 June 2010) BSc, MSc (NZ), PhD (Cantab.) , OBE, FRSNZ, Hon FLS, Hon DSc (Cantuar.) , AHRNZIH was a New Zealand botanist and academic biographer.  He is best known for his long-running series of in the popular magazine "New Zealand Gardener" and his "Biographical notes" series that ran in the "New Zealand Botanical Society Newsletter" and which is the prime resource on the lives of many New Zealand botanists.

Supporting paragraphs: Charles Knight (doctor) Rye
Answer: Rye